In their book Handbook of Christian Apologetics, Peter Kreeft and Ronald K. Tacelli give a summary of faith.
Kreeft and Tacelli say we must distinguish between the act of faith from the object of faith- believing from what is believed. The object of faith means all things believed. For the Christian, this means everything God has revealed in the Bible. This faith (the object, not the act) is expressed in propositions. Propositions are many, but the ultimate object of faith is one. The ultimate object of faith is not words, but God’s Words (singular), indeed-Himself.
Without a relationship with the living God, propositions are pointless, for their point is to point beyond themselves to God. But without propositions, we cannot know or tell others what God we believe in and what we believe about God. They mention a few aspects of faith here:
1. Emotional faith: is feeling assurance or trust or confidence in a person. This includes hope (which is much stronger than a wish and peace (which is much stronger then mere calm.).
2. Intellectual faith: is belief. It is this aspect of faith that is formulated in propositions and summarized in creeds.
3. Volitional faith: is an act of the will, a commitment to obey God’s will. This faith is faithfulness, or fidelity. It manifests itself in behavior, that is, in good works.
Belief That and Belief In
Many Christians object to the use of apologetics. Even though it is all throughout the Bible, in many cases, there seems to be confusion between Belief that and Belief in. Let me explain:
Anyone who does apologetics knows the Holy Spirit has to play an integral part of the entire process. After all, it is impossible to be effective in apologetics without the work of the Spirit in both the apologist and the hearer. Hence, no mature apologist forgets that the Bible stresses that humans are blinded by sin. Therefore, sin has damaging consequences on the knowing process (Is. 6:9-10; Zech. 7:11-12; Matt. 13:10-13; 2 Cor. 4:4). People can be hardened towards God; sin certainly dampens an individual’s ability to being receptive to God’s invitation to them.
Therefore, apologetics may serve as a valuable medium through which God can operate, but the mature apologist knows the issue is never the product of historical facts or evidence alone. For example, in James 2:19, it says that the demons believe that God exists. But just because the demons think God exists, this doesn’t mean they have saving faith. Objectively speaking, apologetics or evidence for God may help someone believe that God exists. However, the individual still needs to place their trust in God. This can only be done with the help of the Holy Spirit (John 16:12-15). Therefore, the apologist knows and prays as well that the Holy Spirit will move the will of the individual to come to the place to have belief that God exists and also trust in him for their salvation.