Because thy promise hath given me encouragement to pray, and assurance of answer. Found in his heart, or, found his heart, i.e. taken courage; as a man is said to lose his heart when he wants courage.
Related Commentaries of 2 Samuel 7:27
2 Samuel 7:27
27 For thou, O LORD of hosts, God of Israel, hast revealedd to thy servant, saying, I will build thee an house: therefore hath thy servant found in his heart to pray this prayer unto thee.