I am not worthy

A centurion was a military officer in the Roman army responsible for the command of a century or a hundred men (Latin centuria, a hundred).

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In Jesus' time, the region of Galilee was not directly ruled by Rome but through a vassal Jewish “king”—Herod Antipas—actually a tetrarch or “ruler of a fourth part” of what used to be the kingdom of Herod the Great.

The officer was probably in the service of Antipas to maintain order in his territory and to see to it that people paid their taxes. For this and for being an “unclean” Gentile, he would be hated by the Galileans. But the man proves to be a remarkable character: he cares for his paralyzed servant and respects the “dividing wall” that separates Jews and Gentiles, and so he feels unworthy to receive Jesus into his house.