1 Samuel 1:11

1:11 She made a vow saying, “O Lord of hosts, if you will look with compassion on the suffering of your female servant, remembering me and not forgetting your servant, and give a male child to your servant, then I will dedicate him to the Lord all the days of his life. His hair will never be cut.”

1 Samuel 17:55

17:55 Now as Saul watched David going out to fight the Philistine, he asked Abner, the general in command of the army, “Whose son is this young man, Abner?” Abner replied, “As surely as you live, O king, I don’t know.”