Judges 21:4

Built there an altar; not for a monument of the victory, as some say, but for sacrifices, as the next words show. Quest. What need was there of this, when the ordinary altar was there, to which also they seem to be restrained, Deuteronomy 16:2 ? Answ. They are not there restrained to one altar, but to one place of worship, as is expressed; and therefore there might be in that place more altars than one, when the multitude of sacrifices so required, which was the case 1 Kings 8:61; and probably at this time, when all the tribes being met, they had many sacrifices to offer, some in common for all, and some peculiar to every tribe. Nay, other altars might be, and ofttimes were, erected in other places, by David, direction or dispensation; as Judges 6:21,26 1 Samuel 7:9,17 1 Samuel 11:15 16:2,5.