Letter 864: Virtue must be practiced with all one's strength — not merely admired from a distance.

To Martinianus. Do not seek wealth, my excellent friend - the father of arrogance, the begetter of contempt, the purveyor of pleasures, the craftsman of every vice, the thing that strips a man of his friendship with God - but seek virtue, which sets one free from all evils. And if it carries sweat and toil with it, do not for that reason shun it, but for that very reason embrace it all the more, reckoning that in all other matters too what is acquired with toil and sweat, even if it happens to be small, is more to be longed for; whereas what falls to us of its own accord is contemptible, even if it should be great.

Μὴ ζήτει πλοῦτον, ὦ βέλτιστε, τὸν τῆς ὑπερηφανίας πατέρα, τὸν τῆς ὑπεροψίας γεννήτορα, τὴν τῶν ἡδονῶν χορηγὸν, τὸν πάσης κακίας δημιουργὸν, τὸν τῆς πρὸς Θεὸν φιλίας ἀποσουλῶντα τὸν ἄνθρωπον· ἀλλ’ αἱρέτην, τὴν πάντων τῶν κακῶν ἀπαλλάττουσαν. Εἰ δὲ ἱδρῶτάς ἔχει καὶ πόνους, μὴ διὰ τοῦτο αὐτὴν ἀποφύγεις, ἀλλὰ διὰ τοῦτο μάλιστα περιπτυξαι, λογιζόμενος, ὅτι καὶ ἐπὶ τῶν ἄλλων πραγμάτων τὸ μετὰ πόνων καὶ ἱδρώτων κτηθὲν, κἂν μικρὸν. τυγχάνῃ, ποθεινότερον ἐστι. Τὸ δ’ αὐτομάτως (47) προσπεσόν, εὐκαταφρόνητον, κἂν ὑπάρχῃ μέγα.