Again, in my view it is way too much to say that Paul is the “Founder of Christianity”: that assumes that he is the one who personally came up with the idea of the importance of the death and resurrection of Jesus for salvation, whereas almost certainly this view had been around for a couple of years before he came onto the scene.  And it is probably too much even to say that he was the “Co-founder of Christianity,” for much the same reason.

But it is safe to say that of all the early Christian thinkers and missionaries, Paul is the one we know best as the one who forcefully advocated this Christian message, in contradistinction to the message of Jesus.  In the writings of Paul more clearly than almost anywhere else in the NT we see that the message *of* Jesus has become the message *about* Jesus: that is, the message that was preached by Jesus during his life was transformed into a message about the importance of his death.

In any event, Jesus and Paul do share similarities as well as differences.  Here is a rough summary:

Similarities of Jesus and Paul:

• Both Jesus and Paul were born and raised Jewish, and neither one of them saw himself as departing from the truth of Judaism and the Jewish God.  They both understood that they were proclaiming the “true” form of Judaism.  Neither of them thought they were staring a “new religion.”
• Both Jesus and Paul proclaimed an apocalyptic message rooted in the categories of Jewish apocalypticism, which understood that the current age was ruled by the forces of evil, but a new age was coming in which God would destroy the forces of evil and bring in a utopian kingdom here on earth.
• Both Jesus and Paul thought that this climactic moment of all human history was soon to come, it was right around the corner, it would be here within their own generation.
• Both Jesus and Paul dismissed what they saw as the Pharisaic concern for the scrupulous observance of the Jewish Law as a way to obtain a right standing before God.
• Both Jesus and Paul taught the ultimate need of faith and saw the love one’s neighbor as the summing up and fulfilling of the law, as the most important thing the followers of God could do.

So, there are a lot of similarities, at a very fundamental level.  But there are also very important and key differences.

Differences Between Jesus and Paul:

• Jesus taught that the coming cosmic judge of the earth who would destroy the forces of evil and bring in God’s good kingdom was a figure that he called the Son of Man, someone other than himself, who could come on the clouds of heaven in a mighty act of judgment.   Paul taught that Jesus himself was the coming cosmic judge of the earth who would destroy the forces of evil and bring in God’s good kingdom, who would come on the clouds of heaven in a mighty act of judgment.
• Jesus taught that to escape judgment, a person must keep the central teachings of the Law as he himself interpreted them.   Paul taught that reliance on the observance of the Law in no sense would bring salvation; to escape the coming judgment a person must, instead, believe in the death and resurrection of Jesus
• Jesus taught that “faith” involves trusting God, as a good parent, to bring his future kingdom to his people; Paul taught that “faith” involves trusting in the past death and resurrection of Jesus.  It wasn’t only faith in God but faith in the death and resurrection of Christ.
• For Jesus, his own importance lay in his proclamation of the coming of the end and his correct interpretation of the Law.  For Paul, Jesus’ importance had nothing to do with Jesus’ own teachings (which Paul hardly ever quotes) but strictly in his death and resurrection.
• For Jesus, people could begin to experience what life would be like in the future kingdom if they would accept his teachings and begin to implement his understanding of the Jewish law in their lives.    For Paul, people could begin to experience life in the kingdom when they “died with Christ” by being baptized and thus overcame the power of sin.

So, are Jesus and Paul more alike or more different?  People come to different conclusions, looking at the same evidence.    I’m afraid there is no right answer, even though many people are quite vociferous in their support of one position or the other.