Agape, in plural, was used by early Christians for their "love feast," a communal meal held in connection with the Lord's Supper. "The loss of their original character and the growth of abuses led to the prohibition of them in church buildings, and in the fourth century to their separation from the Lord's supper and their gradual discontinuance" [Century Dictionary]. In modern use, often in simpler sense of "Christian love" (1856, frequently opposed to eros as "carnal or sensual love").
late Old English, "benevolence for the poor," also "Christian love in its highest manifestation," from Old French charité "(Christian) charity, mercy, compassion; alms; charitable foundation" (12c.), from Latin caritatem (nominative caritas) "costliness; esteem, affection," from carus "dear, valued," from PIE *karo-, from root *ka- "to like, desire."
In the Vulgate the Latin word often is used as translation of Greek agape "love" -- especially Christian love of fellow man -- perhaps to avoid the sexual suggestion of Latin amor). The Vulgate also sometimes translated agape by Latin dilectio, noun of action from diligere "to esteem highly, to love" (see diligence).
Wyclif and the Rhemish version regularly rendered the Vulgate dilectio by 'love,' caritas by 'charity.' But the 16th c. Eng. versions from Tindale to 1611, while rendering agape sometimes 'love,' sometimes 'charity,' did not follow the dilectio and caritas of the Vulgate, but used 'love' more often (about 86 times), confining 'charity' to 26 passages in the Pauline and certain of the Catholic Epistles (not in I John), and the Apocalypse .... In the Revised Version 1881, 'love' has been substituted in all these instances, so that it now stands as the uniform rendering of agape. [OED]
General sense of "affections people ought to feel for one another" is from c. 1300. From c. 1300 as "an act of kindness or philanthropy," also "alms, that which is bestowed gratuitously on a person or persons in need." Sense of "charitable foundation or institution" in English attested by 1690s. Meaning "liberality in judging others or their actions" is from late 15c. A charity-school (1680s) was one maintained by voluntary contributions or bequests.