Leviticus

And the priest answered David, and said, There is no common bread under mine hand, but there is hallowed bread; if the young men have kept themselves at least from women.

And David answered the priest, and said unto him, Of a truth women have been kept from us about these three days, since I came out, and the vessels of the young men are holy, and the bread is in a manner common, yea, though it were sanctified this day in the vessel.

And he said unto the people, Be ready against the third day: come not at your wives.