15 And David would go back and forth from Saul to tend his father’s sheep in Bethlehem.
1 Samuel 17:15 Cross References - ISV
1 Samuel 16:11
11 Then Samuel told Jesse, “Are these all the young men?” He said, “There yet remains the youngest one, and right now he’s tending the sheep.” Samuel told Jesse, “Send someone to get him, for we won’t do anything else until he arrives here.”
1 Samuel 16:19-23
19 So Saul sent messengers to Jesse and said, “Send me your son David, who is with the sheep.”
20 Jesse took a donkey loaded with bread, a container of wine, and one kid, and sent them to Saul along with his son David. 21 David went to Saul and began to serve him. Saul loved him very much, and he became his armor bearer. 22 Saul sent a messenger to Jesse to tell him, “Allow David to serve me, because I’m pleased with him.” 23 Whenever an evil spirit from God came to Saul, David would take the lyre and play it. Relief would come to Saul and he would be better, because the evil spirit would leave him.
20 Jesse took a donkey loaded with bread, a container of wine, and one kid, and sent them to Saul along with his son David. 21 David went to Saul and began to serve him. Saul loved him very much, and he became his armor bearer. 22 Saul sent a messenger to Jesse to tell him, “Allow David to serve me, because I’m pleased with him.” 23 Whenever an evil spirit from God came to Saul, David would take the lyre and play it. Relief would come to Saul and he would be better, because the evil spirit would leave him.