David says, You have visited me by night.
He is referring to lying on his bed, where in quiet thought he considers his life in the light of the Lord’s word (see Psalm 4:4; Psalm 6:6; Psalm 16:7. During such contemplations, God would teach him in the way he should go.1
3 You have tried my heart, you have visited me by night, you have tested me, and you will find nothing; I have purposed that my mouth will not transgress.