“Your "if" is the only peacemaker; much virtue in "if.”

"The Pacific Journal of Adam Ewing", p. 23 (Nook Edition)
Cloud Atlas (2004)

1840s, Essays: First Series (1841), Friendship
Variant: The only way to have a friend is to be one.

H 13
Aphorisms (1765-1799), Notebook H (1784-1788)

Ta vertu met ta gloire au-dessus de ton crime.
Tulle, act V, scene iii.
Horace (1639)

Light (1919), Ch. XVI - De Profundis Clamavi
Context: Men have gone towards each other because of that ray of light which each of them contains; and light resembles light. It reveals that the isolated man, too free in the open expanses, is doomed to adversity as if he were a captive, in spite of appearances; and that men must come together that they may be stronger, that they may be more peaceful, and even that they may be able to live.
For men are made to live their life in its depth, and also in all its length. Stronger than the elements and keener than all terrors are the hunger to last long, the passion to possess one's days to the very end and to make the best of them. It is not only a right; it is a virtue.

The Southern Belle's Handbook: Sissy LeBlanc's Rules to Live By

VIII, line 20.
Compare : We'll shine in more substantial honours, And to be noble we'll be good.
Thomas Percy, Winifreda (1720).
Satires, Satire VI
Variant: Nobility is the one only virtue.

Al-Khisal, p. 4
[Baqir Shareef al-Qurashi, Jasim al-Rasheed, The Life of Imam Muhammad ibn 'Ali al-Baqir, His traditions from the Prophet, 1999]