Exodus 12:22-23

12:22 Take a branch of hyssop, dip it in the blood that is in the basin, and apply to the top of the doorframe and the two side posts some of the blood that is in the basin. Not one of you is to go out the door of his house until morning. 12:23 For the Lord will pass through to strike Egypt, and when he sees the blood on the top of the doorframe and the two side posts, then the Lord will pass over the door, and he will not permit the destroyer to enter your houses to strike you.

Exodus 17:12

17:12 When the hands of Moses became heavy, they took a stone and put it under him, and Aaron and Hur held up his hands, one on one side and one on the other, and so his hands were steady until the sun went down.

Exodus 32:27

32:27 and he said to them, “Thus says the Lord, the God of Israel, ‘Each man fasten his sword on his side, and go back and forth from entrance to entrance throughout the camp, and each one kill his brother, his friend, and his neighbor.’”