Virtue is a gift from God — man is not capable.

Consider how [Jesus Christ] teaches us to be humble, by making us see that our virtue does not depend on our work alone but on grace from on high. He commands each of the faithful who prays to do so universally, for the whole world. For he did not say “thy will be done in me or in us”, but “on earth”, the whole earth, so that error may be banished from it, truth take root in it, all vice be destroyed on it, virtue flourish on it, and earth no longer differ from heaven.

St. John Chrysostom
On the Lord’s Prayer