There are three distinct stages in the meaning of the word ‘lewd;’ of these it has entirely overlived two, and survives only in the third, namely in that of wanton or lascivious. Without discussing here its etymology or its exact relation to ‘lay,’ it is sufficient to observe, that, as ‘lay,’ it was often used in the sense of ignorant, or rather unlearned. Next, according to the proud saying of the Pharisees, ‘This people who knoweth not the law are cursed’ (John vii. 49), and on the assumption, which would have its truth, that those untaught in the doctrines, would be unexercised in the practices, of Christianity, it came to signify vicious, though without designating one vice more than others. While in its present and third stage, it has, like so many other words, retired from this general designation of all vices, to express one of the more frequent, alone.
Archa-Dei in the olde law Levites it kepten;
Hadde nevere lewed man leve to leggen honde on that chest.
Piers Plowman, B-text, Passus xii. 115 (Skeat).
For as moche as the curatis ben often so lewed, that thei understonden not bookis of Latyn for to teche the peple, it is spedful not only to the lewed peple, but also to the lewed curatis, to have bookis in Englisch of needful loore to the lewed people.—Wycliffe Mss., p. 5.
Of sondry thoughtes thus they jangle and trete
As lewed peple demeth comunly
Of thinges that ben maad more subtily
Than they can in her lewdenes comprehende.
Chaucer, The Squieres Tale (Morris, ii. p. 361).