1 Samuel - Chapter 2

Hannah gives a prayer of praise and thanksgiving to God, which is prophetic.

“He will give strength to his king
   and exalt the horn of his anointed.”

This was prayed before there was a king in Israel and is looking ahead to the earthly kings in Israel, and also to the eternal King of Kings who is "the anointed one" - the title Christ is taken from the Greek word christos - which means the anointed one.