Exodus 19:15

Abstain from the use of the marriage-bed, partly because your wives may haply have their uncleanness upon them, though unknown to themselves, at least to you, whereby you may be legally defiled; see Leviticus 15:18; and partly that your minds may be abstracted from all sensual delights, and wholly employed about this great and holy work and service. There is a like command 1 Corinthians 7:5; but both this and that do indifferently concern both ministers and people, and are limited to a certain time, and therefore are very impertinently alleged for the perpetual celibacy of ministers. See also 1 Samuel 21:5.