Judges 15:20
And he judged Israel in the days of the Philistines twenty years.For, lo, thou shalt conceive, and bear a son; and no razor shall come on his head: for the child shall be a Nazarite unto God from the womb: and he shall begin to deliver Israel out of the hand of the Philistines.
Then his brethren and all the house of his father came down, and took him, and brought him up, and buried him between Zorah and Eshtaol in the buryingplace of Manoah his father. And he judged Israel twenty years.