'Serving' in the Bible

And [while] they were serving the Lord and fasting, the Holy Spirit said, "Set apart now for me Barnabas and Saul for the work to which I have called them."

For David, [after] serving the purpose of God in his own generation, fell asleep and {was buried with} his fathers, and experienced decay.

serving the Lord with all humility and with tears, and with the trials that happened to me through the plots of the Jews--

[He] ordered the centurion [for] him to be guarded and to have some freedom, and in no way to prevent any of his own [people] [from] serving him.