'Minister' in the Bible

could my covenant with my servant David and my covenant with the Levites ever be broken. So David will by all means always have a descendant to occupy his throne as king and the Levites will by all means always have priests who will minister before me.

I will make the children who follow one another in the line of my servant David very numerous. I will also make the Levites who minister before me very numerous. I will make them all as numerous as the stars in the sky and as the sands which are on the seashore.'"