'Serve' in the Bible

But if ye shall at all turn from following me, ye or your children, and will not keep my commandments, my statutes which I have set before you, but go and serve other gods, and worship them;

Thy father made our yoke grievous; and now lighten thou the grievous servitude of thy father and his heavy yoke that he put upon us, and we will serve thee.

And they spoke to him saying, If this day thou wilt be a servant to this people, and wilt serve them and answer them and speak good words to them, they will be thy servants for ever.