'Gray headed' in the Bible

And now, behold, the king walks before you. And I am old and gray headed, and, behold, my sons are with you. And I have walked before you from my youth to this day.

With us are both the gray-headed and the very aged men, much older than thy father.

Yea, even when I am old and gray headed, O God, forsake me not, until I have declared thy strength to a generation, thy might to everyone who is to come.