In engaging Muslims with the good news of who Jesus is and what He has done on behalf of sinners, it is helpful to have some background information about the Islamic faith, but it is crucial to understand sound biblical doctrine. Specific Bible teachings that the Christian must understand and be able to present to his or her Muslim friends are: the Trinity, the Person of Christ, the Cross, the Trustworthiness of Scripture, and the Imputed Righteousness of Christ.
Muslims may misunderstand the Christian affirmation of the Trinity, thinking that Christians affirm three gods. Christians must be very clear that there is only one God (Deut 6:4). But we also must proclaim the truth that within the one being that is God, there exists eternally three co-equal and co-eternal Persons: namely, the Father (Matt 6:9), the Word or Son (John 1:1-2; 17:5; Col 2:9), and the Holy Spirit (John 14:26; 15:26; Acts 8:29; 13:2), each with distinct personal attributes (Isa 48:16; Matt 3:16-17; Rom 8:26-27; Heb 9:13-14), but without division of nature, essence or being (John 10:30; 14:9; Acts 5:39). We must readily admit: exactly how the trinity works may be beyond our comprehension, and we must admit that a denial of the trinity may be simpler. But we must challenge our Muslim friends with the question: why should God be so simple that we can completely understand Him?
The Person of Christ
Muslims agree with Christians that Jesus is sinless and that He was sent from God. But Christians must boldly proclaim the truth that Muslims deny: that Jesus Himself claimed to be God (John 10:30). Furthermore, Jesus’ earliest followers claimed that He is God (John 1:1) who took on flesh and dwelt among us (John 1:14) for the purpose of our salvation.
The earliest Christians were eyewitnesses to Jesus’ death (and resurrection), as seen in John 19:32-35, Luke 1:1-4, and 1 Corinthians 15:1-7. Even enemies of Christianity testify to the death of Christ. The earliest Jewish opponents of Christianity did not claim that Jesus had not been crucified (and they admitted that His tomb was empty): Matthew 28:11-15; Josephus, Antiquities, AD 63-64. The earliest Roman opponents of Christianity did not claim that Jesus had not been crucified: Tacitus, AD 115. Modern non-Christian historians do not claim that Jesus was not crucified; Bart Ehrman, who is openly hostile to Christianity, yet stated: “One of the most certain facts of history is that Jesus was crucified on the orders of the Roman prefect of Judea, Pontius Pilate.” Furthermore, the Qur’an itself speaks of the death of Christ in Surah 19:33, though it seems to specifically deny the crucifixion in Surah 4:156-158. Though Muslims deny the crucifixion based on Surah 4:156-158, they do so in contradiction to the eyewitness testimony of the earliest Christians, the testimony of the earliest opponents of Christianity, all sound non-Muslim historical scholarship, and even claims of the Qur’an itself, such as that seen in Surah 19:33.
The Trustworthiness of Scripture
Though Muslim apologists today commonly question the trustworthiness of Christian Scripture, the Qur’an itself, in Surah 10:94, commands Muhammad to “ask those who have been reading Scripture before you” in order that he might relieve his doubts. In context, this Surah is referring to the “Scripture”- the Christian and Jewish Scripture- that came before the giving of the Qur’an. The words of the Qur’an assume, rather than deny, the trustworthiness of Christian Scripture. Christian Scripture is built on eyewitness testimony (see the above in the section on “The Cross”). Christian Scripture is God-breathed (2 Timothy 3:16).
The Imputed Righteousness of Christ
Surah 53:38 asserts: “That no bearer of burdens will bear the burden of another.” This assertion is contradicted by Isaiah 53:4-6, in which the Messiah is proclaimed to be One who bears our griefs, sorrows, afflictions, iniquities, and punishment, being “pierced for our transgressions,” bringing healing to us all. Islam presents an irresolvable problem concerning the justice of God, for how can a holy and righteous God justify the ungodly? This problem is the reason that many Muslims believe that all people spend at least a little time in Hell having their sins burned away before they can enter Heaven. According to the good news of Jesus, this problem is addressed in Romans 3:21-26. God never neglects perfect justice: every sin is paid for, either by the sinner in Hell or by Jesus, in the place of the sinner, upon the Cross. Salvation from sin, death, and Hell is by grace alone through the imputed righteousness of Christ: the one who trusts in Christ is counted righteousness in Christ. Just as Jesus took our sins on Himself while dying on the Cross, the believing sinner takes on the righteousness of the resurrected Christ. This good news of salvation- accomplished by God in Christ on the Cross- glorifies God alone as the only Savior (something that should resonate with our Muslim friends, who say that they are jealous to glorify God alone). The good news of Jesus Christ is summarized in 2 Corinthians 5:21: God made the one who did not know sin [that is, Jesus] to be sin for us, so that in Him we would become the righteousness of God. (NET)