וַיְהִ֣י בְּבוֹאָ֔ם וַיַּ֖רְא אֶת־אֱלִיאָ֑ב וַיֹּ֕אמֶר אַ֛ךְ נֶ֥גֶד יְהוָ֖ה מְשִׁיחֽוֹ׃
And it came to pass, when they were come, that he beheld Eliab, and said: ‘Surely the LORD’S anointed is before Him.’
Rashi on I Samuel
He said, "Surely, before Adonoy is His annointed." He said to himself, 'Surely, it is true that this one is fitting for the kingship.'