'Theirs' in the Bible

and Aaron shall offer the Levites before Yahweh for a wave offering, on the behalf of the children of Israel, that it may be theirs to do the service of Yahweh.

He spoke to the congregation, saying, "Depart, please, from the tents of these wicked men, and touch nothing of theirs, lest you be consumed in all their sins!"

This shall be yours of the most holy things, [reserved] from the fire: every offering of theirs, even every meal offering of theirs, and every sin offering of theirs, and every trespass offering of theirs, which they shall render to me, shall be most holy for you and for your sons.