When you endeavor to share Christ with a Muslim, you are stepping into a true spiritual battle. The average Muslim has great cultural and religious biases against many of the foundational truths of Christianity. For him, the cross is a stumbling block. No other religion hates the cross like Islam, and it is for this reason that you must be prepared not only intellectually, but also in spirit and in attitude before taking up this challenge.
There are three simple, yet vitally important prerequisites we need to examine before moving on to the theological issues involved in sharing Christ with a Muslim.
1. You must be filled with the Holy Spirit€
One of the most critical elements in witnessing to a Muslim is that one must be Spirit-filled. Jesus said in John 15:26, "When the Helper comes, whom I will send to you from the Father, that is the Spirit of Truth, who proceeds from the Father, He will bear witness of me."Success in witnessing is simply sharing the Gospel in the power of the Holy Spirit and leaving the results to God.
I'm sure we could all recount experiences where we've share the Gospel and felt that we were perhaps not filled with the Spirit, but were then amazed to see the person accept Christ. God in His sovereignty works, at times, in spite of us to bring people to Himself. Again, when you are sharing with a Muslim you are engaged in an intense spiritual battle. IF you are not filled with the Spirit of the Lord, you will find yourself quickly exhausted both spiritually and emotionally. I have been in sessions with Muslims where I felt as if I was going to have a heart attack. To give you an example from my own life, I once sat with a Muslim man from Lebanon in a smoke-filled cafe late on evening, trying to explain the Gospel. As we talked, our discussion began to get really heated. The conversation kept going in circles, back and forth, up and down until I thought I was going to explode. At one point, I was so frustrated I thought to myself, "Why can't he understand?" and I literally felt like punching him in the face! I had to remind myself, "You must continue in the power of the Holy Spirit."
Satan would like to let you think that people you are sharing with are just too far from the Kingdom to become Christians, but you must continue. The Holy Spirit gives us wisdom to answer even the most difficult questions asked by Muslims. I was once sharing with a Muslim when he asked me a question that I had not heard before: "Doesn't the Old Testament prophesy about the coming of the Prophet Mohammad?" He quoted a verse from Deuteronomy which I had always known to be about Christ. I immediately asked the Lord to give me wisdom to answer him and started by asking him a question; Does the Koran say that Moses was referring to Mohammad, or are you the one saying that?" He immediately replied that Mohammad did not say in the Koran, "Moses spoke about me". At that moment, the Lord impressed upon me the verse from Luke that says Moses spoke about Jesus:
"He said to them, 'This is what I told you while I was still with you: Everything must be fulfilled that is written about me in the Law of Moses, the Prophets and the Psalms.' " Luke 24:44 Also John 5:46