Over the years I have had plenty of people ask me how to go about sharing their faith with others. They always ask whether they should just go ahead and share their personal testimony. I agree that using a personal testimony can be effective in that it shows the difference that Jesus makes in the reality of life. There is nothing wrong with this. But allow me to offer a few suggestions:
Pragmatism has been one of the most prominent philosophies within American culture over the first quarter of the twentieth century. John Dewey was at the forefront of pragmatism within the educational system. For the pragmatist, an idea is said to be true if it “works” or brings desired results. Pragmatism is not as interested if the idea is objectively true, but simply if an idea leads to expedient or practical results.
God can and does use our testimony in a powerful way. In other words, by sharing our testimony, we want to show that faith in Jesus works; He is responsible for transforming the human heart. While it is true that Jesus changes lives, let me share some examples of personal conversations I have had with several people. I will go ahead and refer to Barry as a common person I encounter on a regular basis.
Eric: “Barry, I want to share with you what Jesus has done in my life. He has transformed my life.”
Barry: “Well that is great, I am happy for you. As long as you are happy, that is fine. But that Jesus thing is not for me.”
Eric: ‘But Barry, he can change your life as well!”
Barry: “Like I said, I am happy the way I am. Furthermore, I don’t see what difference belief in Jesus will really make in my life.”
In a post-modern culture, responses like we see from Barry are becoming more common. But what is interesting is that the transformed life approach is not the primary way the early apostles reached their audience for the Gospel.
First, we should note that the apostles approach to spreading the message of the Gospel is characterized by such terms as “apologeomai/apologia”which means “to give reasons, make a legal defense” (Acts 26:2; 2 Tim. 4:16; 1 Pet 3:15); “dialegomai” which means “to reason, speak boldly” (Acts 17:2; 17; 18:4; 19:8), “peíthō” which means to persuade, argue persuasively” (Acts 18:4; 19:8), and “bebaioō ” which means “to confirm, establish,” (Phil 1:7; Heb. 2:3). 
According to the late F.F. Bruce, the primary way that the apostles established the fact that Jesus was the fulfillment of the promises of the Old Testament Messianic Promises was their appeal to prophecy and miracles  (see more below).
Apologetics in the New Testament
I would like to go ahead and expand on some of the apologetics in the New Testament. Let’s start with the Book of Acts. By the way, to see the post called 84 places, events, people confirmed in The Book of Acts, click here: Anyway, let’s move forward:
Peter said, Men of Israel, listen to these words: Jesus the Nazarene, a man attested to you by God with miracles and wonders and signs which God performed through Him in your midst, just as you yourselves know-this Man, delivered over by the predetermined plan and foreknowledge of God, you nailed to a cross by the hands of godless men and put Him to death.” But God raised Him up again, putting an end to the agony of death, since it was impossible for Him to be held in its power. For David says of Him, I saw the Lord always in my presence; for he is at my right hand, so that I will not be shaken. ‘Therefore my heart was glad and my tongue exulted; moreover my flesh also will live in hope; because you will not abandon my soul to Hades, nor allow your holy one to undergo decay. You have made known to me the ways of life; you will make me full of gladness with your presence.’
Brethren, I may confidently say to you regarding the patriarch David that he both died and was buried, and his tomb is with us to this day. And so, because he was a prophet and knew that God had sworn to him with an oath to seat one of his descendants on his throne, he looked ahead and spoke of the resurrection of the Christ, that he was neither abandoned to Hades, nor did His flesh suffer decay. This Jesus God raised up again, to which we are all witnesses. Therefore having been exalted to the right hand of God, and having received from the Father the promise of the Holy Spirit, He has poured forth this which you both see and hear. “For it was not David who ascended into heaven, but he himself says: the Lord said to my Lord, “sit at my right hand, until I make your enemies a footstool for your feet. Therefore let all the houses of Israel know for certain that God has made Him both Lord and Messiah-this Jesus whom you crucified. Now when they heard this, they were pierced to the heart, and said to Peter and the rest of the apostles, “Brethren, what shall we do?” Peter said to them, “Repent, and each of you be baptized in the name of Jesus for the forgiveness of your sins; and you will receive the gift of the Holy Spirit.-Acts 2: 22-36
We see in this text that the primary apologetic methodology that Peter utilizes is the following: Peter appeals to miracles which have a distinctive purpose: they are used for three reasons:
1. To glorify the nature of God
2. To accredit certain persons as the spokesmen for God
3. To provide evidence for belief in God 
Peter also appeals to:
1. The crucifixion of Jesus
2.Fulfilled prophecy (Jesus had been raised from the dead according to Ps. 16: 8-11 and ascended to heaven in the fulfillment of Ps.110:1).
Let’s look at Acts 3: 11-26:
“While he clung to Peter and John, all the people, utterly astounded, ran together to them in the portico called Solomon’s. And when Peter saw it he addressed the people: “Men of Israel, why do you wonder at this, or why do you stare at us, as though by our own power or piety we have made him walk?The God of Abraham, the God of Isaac, and the God of Jacob, the God of our fathers, glorified his servant Jesus, whom you delivered over and denied in the presence of Pilate, when he had decided to release him. But you denied the Holy and Righteous One, and asked for a murderer to be granted to you, and you killed the Author of life, whom God raised from the dead. To this we are witnesses. And his name—by faith in his name—has made this man strong whom you see and know, and the faith that is through Jesus has given the man this perfect health in the presence of you all.
And now, brothers, I know that you acted in ignorance, as did also your rulers.But what God foretold by the mouth of all the prophets, that his Christ would suffer, he thus fulfilled. Repent therefore, and turn back, that your sins may be blotted out,that times of refreshing may come from the presence of the Lord, and that he may send the Christ appointed for you, Jesus, whom heaven must receive until the time for restoring all the things about which God spoke by the mouth of his holy prophets long ago. Moses said, ‘The Lord God will raise up for you a prophet like me from your brothers. You shall listen to him in whatever he tells you.And it shall be that every soul who does not listen to that prophet shall be destroyed from the people.’ And all the prophets who have spoken, from Samuel and those who came after him, also proclaimed these days. You are the sons of the prophets and of the covenant that God made with your fathers, saying to Abraham, ‘And in your offspring shall all the families of the earth be blessed.’ God, having raised up his servant, sent him to you first, to bless you by turning every one of you from your wickedness.”
We see here that again Peter appeals to:
1.The death and resurrection of Jesus
2.Fulfilled prophecy (in this case, the messianic prophecy of Deut.18: 15-18).
3. Eyewitness Testimony
Acts 4: 8-12
“Then Peter, filled with the Holy Spirit, said to them, “Rulers of the people and elders,if we are being examined today concerning a good deed done to a crippled man, by what means this man has been healed,let it be known to all of you and to all the people of Israel that by the name of Jesus Christ of Nazareth, whom you crucified, whom God raised from the dead—by him this man is standing before you well.This Jesus is the stone that was rejected by you, the builders, which has become the cornerstone.And there is salvation in no one else, for there is no other name under heaven given among me by which we must be saved.”
Peter appeals to:
- The death and resurrection of Jesus
- Fulfilled prophecy (Ps. 118:22)
Acts 7-Stephen’s Speech
Stephen appeals to fulfilled prophecy when he says.
“Which of the prophets did your fathers not persecute? And they killed those who announced beforehand the coming of the Righteous One, whom you have now betrayed and murdered, you who received the law as delivered by angels and did not keep it.”-Acts 7:52
When Phillip is witnessing to the Ethiopian Eunuch, he appeals to fulfilled prophecy. In this case he cites Isa. 53 (see Acts 8:26-40).
In his sermon at Pisidian Antioch (Acts 13: 16-41), Paul says Jesus is the fulfillment of the Davidic Covenant.
Paul also says Jesus is the fulfillment of Ps. 2:7 and 16:10 (see Acts 13:33-37).
Let me mention some other Pauline passages:
“Now I make known to you, brethren, the gospel which I preached to you, which also you received, in which also you stand, by which also you are saved, if you hold fast the word which I preached to you, unless you believed in vain. For I delivered to you as of first importance what I also received, that Christ died for our sins according to the Scriptures, and that He was buried, and that He was raised on the third day according to the Scriptures, and that He appeared to Cephas, then to the twelve. After that He appeared to more than five hundred brethren at one time, most of whom remain until now, but some have fallen asleep; then He appeared to James, then to all the apostles; and last of all, as to one untimely born, He appeared to me also” (1 Corinthians 15:1-17).
We see here:
1.The Messiah died according to the Jewish Scriptures (most likely Isa. 53:1-2; Ps. 22).
2.He was raised according to the Scriptures (Isa. 53; Ps.16:8-11).
Let’s look at Romans 1:1-7:
“Paul, a bond-servant of Christ Jesus, called as an apostle, set apart for the gospel of God, which He promised beforehand through His prophets in the holy Scriptures, concerning His Son, who was born of a descendant of David according to the flesh, who was declared the Son of God with power by the resurrection from the dead, according to the Spirit of holiness, Jesus Christ our Lord, through whom we have received grace and apostleship to bring about the obedience of faith among all the Gentiles for His name’s sake, among whom you also are the called of Jesus Christ; to all who are beloved of God in Rome, called as saints:Grace to you and peace from God our Father and the Lord Jesus Christ.”
We see that:
1 Paul says that the information about the coming Messiah was written about beforehand in the Jewish Scriptures.
2. Paul says through the resurrection, Jesus is installed (by God) as the Son of God (Rom. 1:4). Paul is not saying Jesus is being appointed as The Son of God is a change in Jesus’ essense. The appointment is not in terms of his nature but in terms of his work as a mediator—the messianic age has dawned. Jesus is the Lord—the anti-type of the previous “sons” in the Old Testament (Adam, David, Israel).
3. Remember, the New Testament authors unanimously declare Jesus as the one who is from the “seed of David,” sent by God to restore God’s kingship over mankind (Matt. 1:1; Acts 13:23; Rom. 1:3,4; 2 Tim:2:8; Rev. 22:16). As seen in 2 Samuel 7:12-17, the immediate prophecy is partially fulfilled in David’s son Solomon. However, the word “forever” shows there are future descendants to come. God promised David that his “seed” would establish the kingdom. There were two ways for this prophecy to come to pass. Either God could continually raise up a new heir or he could have someone come who would never die. Does this sound like the need for a resurrection?
“Paul went into the synagogue reasoning and giving evidence that the Messiah had to suffer and rise again from the dead.”
In this passage, Paul appeals to fulfilled prophecy which is probably a reference to Isa. 53:1-12; Ps. 22:1-16;16.
If we go on to read about how Paul dealt with his audience at Mars Hill we see the following. As he is speaking to his audience towards the end of the chapter he says the following:
“Therefore having overlooked the times of ignorance, God is now declaring to men that all people everywhere should repent, because He has fixed a day in which He will judge the world in righteousness through a Man whom He has appointed, having furnished proof to all men by raising Him from the dead.” (Acts 17:30-31).
What stands out here:
(1) Paul is urgent in his appeal for repentance
(2) According to Acts 14: 26, Paul states there was “a time in which God allowed the nations to walk in their own ways,” but now Paul states in Acts 17: 30, “The times of ignorance is over” – God has given man more revelation in the person of Jesus the Messiah
(3) Paul uses the same language as is used in the Jewish Scriptures about judgment (Psalm 9:9)
(4) The judgment will be conducted by an agent, a man who God has appointed
(5) Paul treats the resurrection as an historical fact and he uses it as a proof of God’s appointment as Jesus as the judge of the living and the dead! 
Finally, let me finish with 1 Peter 1:10-12
“Concerning this salvation, the prophets who prophesied about the grace that was to be yours searched and inquired carefully, inquiring what person or time the Spirit of Christ in them was indicating when he predicted the sufferings of Christ and the subsequent glories. It was revealed to them that they were serving not themselves but you, in the things that have now been announced to you through those who preached the good news to you by the Holy Spirit sent from heaven, things into which angels long to look.”
We see here that the prophets were aware of five facts:
1. The Messiah would come
2. The Messiah would need to suffer
3. The Messiah would be glorified
4. This message had been revealed to the prophets not only for their own day, but also for a future generation such as the community of Peter’s audience.
5. Although they knew they wrote about the Messiah, they wish they had knowledge of the time of these things.
In conclusion, E.H. Dewart summarized the apostles’ use of Messianic prophecy :
“In all this there was an appeal…to the things that had been foretold by the prophets and fulfilled by the events of the life and death of Jesus of Nazareth. It is evident that Peter and Paul had strong confidence in the evidential value of fulfilled prediction.”
So to summarize “The Kerygma” of the early Christian community:
1. The promises by God made in the Hebrew Bible/The Old Testament have now been revealed with the coming of Jesus the Messiah (Acts 2:30;3;19;24,10:43; 26:6-7;22).
2. Jesus was anointed by God at his baptism (Acts 10:38).
3. Jesus began his ministry at Galilee after his baptism (Acts 10:37).
4. Jesus conducted a beneficent ministry, doing good and performing mighty works by the power of God ( Acts 2:22; 10:38).
5. The Messiah was crucified according to the plan of God (Acts 2:23).
6. He was raised from the dead and appeared to his disciples (Acts 2:24; 31-32; 3:15-26;10:40-41;17:31;26:23).
7. Jesus was exalted and given the name “Lord” (Acts 2:25-29;33-36;3:13;10:36).
8. He gave the Holy Spirit to form the new community of God (Acts 1:8;2;14-18;33,38-39;10:44-47).
9. He will come again for judgment and the restoration of all things (Acts 3:20-21;10:42; 17:31).
10. All who hear the message should repent and be baptized because of the finished work of Jesus (Acts 2:21;38;3:19;10:43, 17-48; 17:30, 26:20).
As Bruce says again:
The apostolic preaching was obliged to include an apologetic element if the stumbling-block of the cross was to be overcome; the kerygma . . . must in some degree be apologia [cf. 1 Cor. 1:17-25; 2:1-5]. And the apologia was not the invention of the apostles; they had “received” it–received it from the Lord [Luke 24:44-53; Acts 1:8]. To begin with, the cross had been a stumbling-block to themselves, until He appeared to them in resurrection and asked the question: “Was it not necessary that the Christ should suffer these things and enter into His glory?” (Luke 24:26). Necessary indeed, because thus it was written; and so, “beginning with Moses and all the prophets, He interpreted to them in all the Scriptures the things concerning Himself” (Luke 24:27). And Paul, who had “received” this account of the death of Christ among the things “of first importance” [1 Cor. 15:1-11], was able ac cordingly in later days to tell a Jewish king that in his apostolic ministry he said “nothing but what the prophets and Moses said would come to pass: that the Christ must suffer, and that, by being the first to rise from the dead, He would proclaim light both to the people and to the Gentiles” (Acts 26:23). (6)
I will admit that anyone who tries to understand how the apostles used messianic prophecy will also need to understand the hermeneutical methods of that period. I have not gone over that in great detail in this post. One helpful resource on this topic is Michael Rydelnick’s The Messianic Hope: Is The Hebrew Bible Really Messianic?
However, my hope and prayer is that that Christians will see that one of the main apologetic approaches the Holy Spirit used to grow and expand the early Church was an evidential method. And remember the role of prayer in The Book of Acts.
Perhaps we can conclude with the words of J.P. Moreland:
“Today, we share the gospel as a means of addressing felt needs. We give testimonies of changed lives and say to people if they want to become better parents or overcome depression or loneliness, that the Jesus is their answer. This approach to evangelism is inadequate for two reasons. First, it does not reach people who may be out of touch with their feelings. Second, it invites the response, “Sorry, I do not have a need.” Have you noticed how no one responded to Paul in this manner? In Acts 17-20, he based his preaching on the fact that the gospel is true and reasonable to believe. He reasoned and tried to persuade people to intelligently accept Jesus.” 
 Garrett J. Deweese, Doing Philosophy as a Christian (Downers Grove, ILL: IVP Publishers, 2012), 78-79.
 F.F. Bruce, A Defense of the Gospel in the New Testament (Grand Rapids, MI: Eerdmans, 1988), 74-75.
 Norman Geisler, Baker Encyclopedia of Christian Apologetics ( Grand Rapids, MI: Baker Books, 1999), 45
 I. Howard Marshall, The Acts of the Apostles (Tyndale New Testament Commentaries. Grand Rapids: MI: Intervarsity Press. 1980), 288-290.
 E.H. Dewart, Jesus the Messiah in Prophecy and Fulfillment: A Review and Refutation of the Negative Theory of Messianic Prophecy (Cincinnati” Cranston and Stowe; New York: Hunt and Eaton, 1891), 217-218;cited in Darrell L. Bock and Mitch Glaser, To The Jew First: The Case For Jewish Evangelism In Scripture And History (Grand Rapids, MI: Kregal Publications, 2008), 269.
 Bruce. 18-19.
 J.P Moreland, Love Your God With All Your Mind. Colorado Springs, CO: NavPress. 1997, pg 30