A dictionary of Proverbs (Oxford Paperback Reference)

ENOUGH is enough
From its older use as an expression of content or satisfaction (cf. ENOUGH is as good as a feast), this is now frequently used as a reprimand, warning someone off from persisting in an inappropriate or excessive course of action.

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  1546 J. HEYWOOD Dialogue of Proverbs II. xi. Ml Sens enough is enough (sayd I) here maie we With that one word take end good. 1832 W. IRVING Alhambra II. 40 ‘I will descend for no more,’ said the Moor, doggedly; ‘enough is enough for a reasonable man —more is superfluous.’ 1915 T. DREISER Titan (ed. 3) xlvii. 404 I realize all its merits just as well as you do. But enough is enough. 2007 New Scientist 20 Oct 59 Also then I’d get talking about people that I still see, and I didn’t think much would be gained by it.. Enough is enough. ■ content and discontent; moderation
  

enough see also throw DIRT enough, and some will stick; give a man ROPE enough and he will hang himself; a WORD to the wise is enough.
envied see BETTER be envied than pitied.
equal see DOGS look up to you, cats look down on you, pigs is equal.
To ERR is human (to forgive divine)
Although known in Latin (humanum est errare, it is human to err) and in earlier English versions, this saying is generally quoted in Pope’s words (quot. 1711). Cf. c 1386 CHAUCER Tale of Melibee 1.1264 The proverbe seith that ‘for to do synne is mannyssh, but certes for to persevere longe in synne is werk of the devel’; 1539 R. MORISON tr. J. L. Vives’ Introduction to Wisdom D7 It is naturally gyuen to al men, to erre, but to no man to perseuer.. therein.

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  1578 H. WOTTON tr. J. Yver’s Courtly Controversy E3 To offend is humaine, to repent diuine, and to perseuere diuelish. 1659 J. HOWELL Proverbs (French) 12 To erre is humane, to repent is divine, to persevere is Diabolicall. 1711 POPE Essay on Criticism 1. 525 Good-Nature and Good-Sense must ever join; To Err is Humane; to Forgive, Divine. 1908 Times Literary Supplement 27 Mar. 1 The modern moralist pardons everything, because he is not certain of anything, except that to err is human. 2000 T. DALRYMPLE Life at Bottom (2001) 222 To err is human, to forgive divine: and the police have now taken up the role of divinities, making allowances for wrongdoers instead of apprehending them. "forgiveness; wrong-doers