'Convincing' in the Bible

and they saw [a manifestation of] the God of Israel; and under His feet there appeared to be a pavement of sapphire, just as clear as the sky itself.

To these [men] He also showed Himself alive after His suffering [in Gethsemane and on the cross], by [a series of] many infallible proofs and unquestionable demonstrations, appearing to them over a period of forty days and talking to them about the things concerning the kingdom of God.