Adam Clarke on Psalms 3:5

I laid me down and slept - He who knows that he has God for his Protector may go quietly and confidently to his bed, not fearing the violence of the fire, the edge of the sword, the designs of wicked men, nor the influence of malevolent spirits.

I awaked - Though humanly speaking there was reason to fear I should have been murdered in my bed, as my most confidential servants had been corrupted by my rebellious son; yet God, my shield, protected me. I both slept and awaked; and my life is still whole in me.