'Serving' in the Bible

So Bathsheba went to the king in his bedroom. Since the king was very old, Abishag the Shunammite was serving him.

Geber the son of Uri, in the land of Gilead, the country of Sihon king of the Amorites and of Og king of Bashan; and he was the only officer who was in the land.

And Solomon hath been ruling over all the kingdoms, from the River to the land of the Philistines and unto the border of Egypt: they are bringing nigh a present, and serving Solomon, all days of his life.

Then King Rehoboam consulted with the old men who had been {serving} before Solomon his father when he was alive, saying, "How [are] you advising [me] {to answer this people}?"

But he rejected the advice of the old men, which they gave him, and he consulted with the youngsters who had grown up with him, who were {serving} before him.