Nicene and Post-Nicene Fathers, Vol. II:
City of God: Chapter 14

Chapter 14.—Whether Men, Though Mortal, Can Enjoy True Blessedness.

It is a great question among men, whether man can be mortal and blessed.  Some, taking the humbler view of his condition, have denied that he is capable of blessedness so long as he continues in this mortal life; others, again, have spurned this idea, and have been bold enough to maintain that, even though mortal, men may be blessed by attaining wisdom.  But if this be the case, why are not these wise men constituted mediators between miserable mortals and the blessed immortals, since they have blessedness in common with the latter, and mortality in common with the former?  Certainly, if they are blessed, they envy no one (for what more miserable than envy?), but seek with all their might to help miserable mortals on to blessedness, so that after death they may become immortal, and be associated with the blessed and immortal angels.