1 Samuel 16:6-7

So it happened, when they had come, he looked at Eliab [the eldest son] and thought, “Surely the LORD’S anointed is before Him.” But the LORD said to Samuel, “Do not look at his appearance or at the height of his stature, because I have rejected him. For the LORD sees not as man sees; for man looks at the outward appearance, but the LORD looks at the heart.”