'Serve' in the Bible

For thy servant vowed a vow while I abode at Geshur in Syria, saying, If Jehovah shall indeed bring me again to Jerusalem, then I will serve Jehovah.

And again, whom should I serve?'should I not'serve in the presence of his son? as I have served in thy father's presence, so will I be in thy presence.

Thou also hast delivered me from the strivings of my people; Thou hast kept me to be the head of the nations: A people whom I have not known shall serve me.