'Therein' in the Bible

Let heavier work be laid on the men, that they may labor therein; and don't let them pay any attention to lying words."

You shall keep the Sabbath therefore; for it is holy to you. Everyone who profanes it shall surely be put to death; for whoever does any work therein, that soul shall be cut off from among his people.

You shall set the basin between the Tent of Meeting and the altar, and shall put water therein.

He set the basin between the Tent of Meeting and the altar, and put water therein, with which to wash.