'Minister' in the Bible

Also the foreigners who join themselves to Yahweh, to minister to him, and to love the name of Yahweh, to be his servants, everyone who keeps the Sabbath from profaning it, and holds fast my covenant;

All the flocks of Kedar shall be gathered together to you, the rams of Nebaioth shall minister to you; they shall come up with acceptance on my altar; and I will glorify the house of my glory.

"Foreigners shall build up your walls, and their kings shall minister to you: for in my wrath I struck you, but in my favor have I had mercy on you.