"A most astonishing misconception has long dominated the modern mind on the subject of St Paul. It is to this effect: that Jesus preached a kindly and simple religion (found in the Gospels) and that St Paul afterwards corrupted it into a cruel and complicated religion (found in the Epistles). This is really quite untenable. All the most terrifying texts come from the mouth of Our Lord: all the texts on which we can base such warrant as we have for hoping that all men will be saved come from St Paul." CS Lewis Introduction to JB Phillip's Letters to Young Churches.
I have long used the JB Phillips paraphrase of the New Testament (which came later than this book, which is partial), largely on Lewis's affection for it. Fundamentalists get all nervous about paraphrases, thinking that they are not reliable or trustworthy, somehow. How dare you paraphrase the BIBLE? Even evangelicals get affected by this. Yet anyone who has ever translated from one language to another or even dealt heavily with translations knows that paraphrase is far more accurate in meaning than trying to make sure that the combination of letters that came down to us textus receptus is the true and shining Word of God. Having those exact words is a good check on going too far astray, and correcting our work. But literal translations are horribly misleading. Every language has idioms and phrasings that in their literal versions make no sense. What does it mean to "get your act together," or to "pull someone's leg," or to "hit the sack?" At every moment in reading Hebrew or Greek there is some danger of this. Hopefully, we have smoothed these out over time with scholarship and common sense. Yet are we absolutely sure of that?
We might laugh at these in heaven, saying "Amos! I thought you meant something completely different! This is hysterical." That is why we should hold such things lightly now, doing the best we can to muddle through with what we've got. The long meaning, verse after verse or repeated many times in the scriptures should command our greatest attention, and puzzling things should be regarded as...puzzling and...intriguing. They should in no way be discarded. They may someday reveal a meaning to us that is key to our understanding. But we should be humble about texts.
As to gentle Jesus and harsh Paul, there is Matthew 10. This is troubling to read.