'Gray headed' in the Bible

And now, behold, the king walketh before you; and I am old and grayheaded; and, behold, my sons are with you: and I have walked before you from my youth unto this day.

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

Yea, even when I am old and grayheaded, O God, forsake me not, Until I have declared thy strength unto the next generation, Thy might to every one that is to come.