Why Did Jesus Bother Ministering Before Sacrificing Himself?

Paul's whole ministry makes no sense if we consider that because Paul came, we did not need Jesus.

Why did Jesus bother hanging around with his disciples for three and a half years if he could just reveal everything to Paul? Why not just be sacrificed and then preach the word everywhere?

While on Earth, Jesus never once mentioned (or hinted) that he would give new revelations to anyone. Especially not to a Pharisee. Instead, he said, For I have given unto them the words which thou gavest me; and they have received them and have known surely that I came out from thee, and they have believed that thou didst send me.^{John 17:8} Jesus gave the disciples all the words that God told him to.

Value of this Evidence

This is decent evidence for Paul being a false apostle. Assuming that Paul is not lying, Jesus could have spoken more for a few reasons, which we need not elaborate here. However, the question is an intriguing one, and brings into mind whether Jesus's work was finished, when he said, it is finished.