'Watch' in the Bible

So Jehu, the son of Jehoshaphat, the son of Nimshi, made designs against Joram. (Now Joram and all the army of Israel were keeping watch on Ramoth-gilead because of Hazael, king of Aram:

And he gave them orders, saying, This is what you are to do: the third part of you, who come in on the Sabbath and keep the watch of the king's house,

And the two divisions of you, who go out on the Sabbath and keep the watch of the house of the Lord,