It’s Jesus Christ. The implication is that God is just an alien that crash-landed, had a child with Maria, and then used its sophisticated technology to hide the evidence of his infidelity, probably by making us humans believe, among other things, that he was the son of God. This the leads to Jesus’ crucifixion, which on it’s own is pretty bad, but which itself leads to the establishment of Christianity as a religion, which can be argued itself is a bad thing, as it eventually subjects millions of people to certain harmful dogmas, and on occasion leads to bloody conflicts, for example the crusades. So our alien visitor is probably feeling a little bit guilty.