'Serving' in the Bible

Thanks be to God through Jesus Christ our Lord! So then, on the one hand I myself with my mind am serving the law of God, but on the other, with my flesh the law of sin.

if service, in his serving; or he who teaches, in his teaching;

not lagging behind in diligence, fervent in spirit, serving the Lord;

but now, I am going to Jerusalem serving the saints.