There is a warrior, at the height of his power, forty years old, who is not like a sixty-year-old, nor a sixty-year-old like a seventy-year-old, but the older he grows the more his power wanes. Not so, He who spoke and brought the world into being — (Malachi 3:6) "I am the L–rd. I have not changed!
There is a warrior, at the height of his power, forty years
Mekhilta Tractate Shirah 4:7