Genesis 21:15

She cast the child. As noted previously, Ishmael was no longer an infant but a grown lad. The word translated “child” is sometimes rendered “young man” (see Gen. 4:23; 1 Kings 12:10). The word “cast,” although seeming to suggest rough treatment, must be understood as in Matt. 15:30, where the sick were “cast” at Jesus’ feet to be healed. This implies only that they were committed to His solicitous care. Hagar committed Ishmael to the shade of the tree, the only available means of relieving his pain. In translating the Hebrew “cast” into Greek, the LXX uses the same word as does Matthew. Though despairing of his life, the mother took care that he should at least breathe out his life in the shade; it was all she could do for him.