'Served' in the Bible

When all the kings serving Hadadezer saw that they had been defeated by Israel, they made peace with Israel and served them. So the Arameans (Syrians) were afraid to help the Ammonites anymore.

Instead, he called his young man who was his personal servant and said, “Now throw this woman out of my presence and bolt the door behind her.”

Besides, whom should I serve? Should I not serve in the presence of David’s son? As I have served in your father’s presence, so I shall serve in your presence.”

“You also have rescued me from strife with my [own] people;You have kept me as the head of the nations.People whom I have not known served me.