12 So she helped him climb out through a window, and he fled and escaped. 13 Then she took an idol and put it in his bed, covered it with blankets, and put a cushion of goat's hair at its head. 14 When the troops came to arrest David, she told them he was sick and couldn't get out of bed. 15 But Saul sent the troops back to get David. He ordered, "Bring him to me in his bed so I can kill him!" 16 But when they came to carry David out, they discovered that it was only an idol in the bed with a cushion of goat's hair at its head. 17 "Why have you betrayed me like this and let my enemy escape?" Saul demanded of Michal. "I had to," Michal replied. "He threatened to kill me if I didn't help him."
18 So David escaped and went to Ramah to see Samuel, and he told him all that Saul had done to him. Then Samuel took David with him to live at Naioth.
Matthew Henry's Commentary on 1 Samuel 19:12-18
Commentary on 1 Samuel 19:11-24
(Read 1 Samuel 19:11-24)
Michal's stratagem to gain time till David got to a distance was allowable, but her falsehood had not even the plea of necessity to excuse it, and manifests that she was not influenced by the same spirit of piety which had dictated Jonathan's language to Saul. In flying to Samuel, David made God his refuge. Samuel, as a prophet, was best able to advise him what to do in this day of distress. He met with little rest or satisfaction in Saul's court, therefore went to seek it in Samuel's church. What little pleasure is to be had in this world, those have who live a life of communion with God; to that David returned in the time of trouble. So impatient was Saul after David's blood, so restless against him, that although baffled by one providence after another, he could not see that David was under the special protection of God. And when God will take this way to protect David, even Saul prophesies. Many have great gifts, yet no grace; they may prophesy in Christ's name, yet are disowned by him. Let us daily seek for renewing grace, which shall be in us as a well of water springing up into everlasting life. Let us cleave to truth and holiness with full purpose of heart. In every danger and trouble, let us seek protection, comfort, and direction in God's ordinances.