"But ye have not so learned Christ; if so be that ye have heard Him, and have been taught by Him, as the truth is in Jesus: that ye put off, concerning the former conversation, the old man (not the hoary man, but him that is) corrupt according to deceitful lusts; and be renewed (not by dyeings and ornaments), but in the spirit of your mind; and put on the new man, which after God is created in righteousness and true holiness.".
Renovamini autem spiritu mentis vestrae, et induatis novum hominem, qui creatus est secundum Deum in justitia et sanctitate veritatis"
To believe in Christ is to obtain immortality and receive eternal life. For he himself is life. He himself is light. He himself is eternity. He himself is the one who overcomes death. He has by overcoming death overcome us too through the fulfilled mystery of salvation. –.
The expression, If so be that you heard Him, is not that of one doubting, but of one even strongly affirming: as he also speaks elsewhere, If so be that it is a righteous thing with God to recompense affliction to them that afflict you. 2 Thessalonians 1:6 That is to say, It was not for these purposes that ye learned Christ.