Muslims like to cast doubt on the apostle Paul and his writings; and they like to use liberal scholarship. Paul Bilal Williams likes to use James D. G. Dunn a lot in his polemics against the New Testament and against the crucifixion and the resurrection of Jesus Al Masih.
James D. G. Dunn on the apostle Paul’s testimony in 1 Corinthians 15:1-9 – “This tradition, we can be entirely confident, was formulated as a tradition within months of Jesus’ death.” Jesus Remembered, page 855. (some online sources that are quoting this, say the page number is 825, but I have the electronic version of Jesus Remembered and it is on page 855.
Interesting that Paul B. Williams’ favorite NT scholar affirms 1 Corinthians 15! (No longer there, as P. B. William’s has changed his websites several times.)
1 Corinthians 15
New American Standard Bible (NASB)
The Fact of Christ’s Resurrection
15 Now I make known to you, brethren, the gospel which I preached to you, which also you received, in which also you stand, 2 by which also you are saved, if you hold fast the word which I preached to you, unless you believed in vain.
3 For I delivered to you as of first importance what I also received, that Christ died for our sins according to the Scriptures, 4 and that He was buried, and that He was raised on the third day according to the Scriptures, 5 and that He appeared to Cephas, then to the twelve. 6 After that He appeared to more than five hundred brethren at one time, most of whom remain until now, but some have fallen asleep; 7 then He appeared to James, then to all the apostles; 8 and last of all, as to one untimely born, He appeared to me also. 9 For I am the least of the apostles, and not fit to be called an apostle, because I persecuted the church of God. 10 But by the grace of God I am what I am, and His grace toward me did not prove vain; but I labored even more than all of them, yet not I, but the grace of God with me. 11 Whether then it was I or they, so we preach and so you believed.