A) Every Christian should be critical of Paul. Paul never met Jesus in his life, and in his life he has been bounty hunter on Christians .Immediately after his ascension Paul joins the inner circle of Jesus which was taken by his disciples like Peter with suspicion. Then Paul negated the teachings of Jesus through entering his contradictions over and above teachings of Jesus. Here is the link.
Jesus said there will be many imposters who will come after me and Bible tells their sign is that they will contradict previous messengers and their teachings. Paul is the one who contradicts teachings of Jesus. While Prophet Muhammad glorified Jesus. Quran acknowledges his work and glorifies him. Quran says “Don’t discriminate among the messengers of Allah” so for Muslim both Jesus Christ and Prophet Muhammad are on the same page same level of respect. Difference is that Jesus said and Bible says he came for only Jews and none else while Prophet Muhammad says and Quran confirms that he came for whole mankind.