For those that are interested in discussing truth claims with Mormons, and Muslims, this is helpful:
“If we are to perceive and approve the divine character of Scripture, nothing less than the work of the Holy Spirit is required. The work of the Spirit in enabling us to hear Scripture as God’s word can be seen in two parts: illumination and demonstration. First, the Holy Spirit illumines or opens our mind to behold the divine excellence that is contained in Scripture. He regenerates our noetic faculties such that we are able to hear the words of Scripture as God’s personal message to us. In essence, the Spirit as the divine author of the text opens the text to us. Second, the Holy Spirit demonstrates or testifies to the truth of Scripture. In 1 Corinthians 2:4-14 and 1 Thessalonians 1:5, Paul attributes the persuasive and convicting power of the gospel to the testimony of the Holy Spirit. The testimony of the Spirit then provides us with the certainty that Scripture is indeed the word of God. Calvin remarks, If we desire to provide in the best way for our consciences — that they may not be perpetually beset by the instability of doubt or vacillation, and that they may not also boggle at the smallest quibbles — we ought to seek our conviction in a higher place than human reasons, judgments, or conjectures, that is, in the secret testimony of the Spirit.59 The certainty afforded by the Holy Spirit is not a formal certainty; it is not self-evident or incorrigible in the sense that 1 + 1 = 2. Rather, it is a moral certainty that gives one cognitive rest or peace regarding the divine authority of Scripture.
The testimony of the Holy Spirit also plays a vital part in affirming the authenticity of the Book of Mormon. Moroni exhorts his followers “that ye would ask God, the Eternal Father, in the name of Christ, if these things are not true; and if ye shall ask with a sincere heart, with real intent, having faith in Christ, he will manifest the truth of it unto you, by the power of the Holy Ghost. And by the power of the Holy Ghost ye may know the truth of all things” (Moro 10:4-5). When honest truth seekers cry out in their hearts to God concerning the truth of the things recorded in the Book of Mormon, he will “speak peace to [their minds] concerning the matter” (D&C 6:23). Despite the similar function, the content of the testimony of the Holy Spirit in Mormonism differs from evangelical Christianity. Evangelical Christians believe that the Spirit does not add to, modify, or contradict Scripture; the Spirit witnesses to the Word, not against it or in addition to it. Mormons, however, hold that the ultimate source of knowledge “is linked not to written words, not even to the writings of Moses or Isaiah or Malachi, not to the four Gospels or the epistles of Paul, but rather to the spirit of prophecy and revelation.” Consequently, the Spirit does not so much testify to the Bible, or the Book of Mormon, as to its ongoing revelation. But this creates the problem of a continuous circular argument. If new revelation is needed to attest to the revelation in the Book of Mormon, then further revelation is needed to attest to this new revelation. Islam has no notion of the Holy Spirit. It nevertheless does have some form of…cry, recognizing that what they heard was the clear truth of God’s word (5:83; 17:107-9; 32:15; 84:21). Another passage speaks of a tingling sensation in the skin and the softening of the heart (39:23). The sacrality of the qurʾanic recitation is incipient in the Qurʾan. Later Islamic thought, however, developed and embellished stories of spontaneous conversion, stories in which unbelievers and even those hostile to the prophet responded positively upon hearing the recitation of the Qurʾan.70 Regardless of how Muslims epistemologists interpret this religious experience, we should note that the Christian appeal to the testimony of the Spirit is not an appeal to a person’s experience, emotions, intellect, or inner consciousness — it is an appeal directly to God. This witness is not a witness borne by our consciousness, but a witness to our consciousness by the Spirit. The witness of the Spirit does provide a feeling or experience of cognitive rest, but the existence of this experience is not the premise of an argument, but the occasion, for the formation of our belief that Scripture is indeed the word of God.”—Knowing the Bible Is the Word of God Despite Competing Claims Te-Li Lau. Featured in The Enduring Authority of the Christian Scriptures by D. A. Carson