2 Samuel 6:1

Again, David gathered together all [the] chosen [men] of Israel, thirty thousand. Which was done by the advice of his officers, 1 Chronicles 13:1; the word "again" refers either to the gathering of them when they made him king in Hebron, as the Jewish writers generally observe; but then they gathered themselves, and not David: or rather to his gathering them to fight the Philistines a little while ago; and as they were the choice and young men that were gathered for war, as being the fittest, so now to fetch up the ark with dancing and singing, and to protect it; the Septuagint version says they were about seventy thousand; but the Targum, Syriac, and Arabic versions, have thirty thousand, agreeably to the Hebrew text.