'Serve' in the Bible

Are they not all ministering spirits, sent out to serve those who will inherit salvation?

For God is not unjust so as to forget your work and the love you have demonstrated for his name, in having served and continuing to serve the saints.

The place where they serve is a sketch and shadow of the heavenly sanctuary, just as Moses was warned by God as he was about to complete the tabernacle. For he says, "See that you make everything according to the design shown to you on the mountain."

We have an altar that those who serve in the tabernacle have no right to eat from.