'Theirs' in the Bible

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

And he spake unto the congregation, saying, Depart, I pray you, from the tents of these wicked men, and touch nothing of theirs, lest ye be consumed in all their sins.

This shall be thine of the most holy things, reserved from the fire: every oblation of theirs, even every meal-offering of theirs, and every sin-offering of theirs, and every trespass-offering of theirs, which they shall render unto me, shall be most holy for thee and for thy sons.