There is a little known scripture known as the Testaments of the Twelve Patriarchs. It is implicitly quoted or at least used as a sacred source by the Apostle Paul (R H Charles, translator of the Book of Enoch claimed) and so it seems to be genuinely ancient and trustworthy. It mentions the Books of Enoch (the Book of Enoch is a collection of books) existing at the time of Abraham and the sons of Jacob. It has a prophecy in it that perfectly describes the baptism of Jesus, explaining the holy signs which marked it. It seems this is a foretelling of that baptism since the use of the scripture by Paul as a source and his apparent reliance on its trustworthiness would place it before Christ came.
