Ps. 17:3 You have tested my thoughts and examined my heart in the night. You have scrutinized me and found nothing amiss, for I am determined not to sin in what I say.
What a testimony! The Lord tested David's thought life and found nothing amiss. I wonder how many of us can say the same thing. No one can see what we think about, but we and God know. We tend to forget the fact that it does matter what we dwell on. Whenever we think about things that are unholy or lead us into sin, we need to take it seriously. We are admonished to dwell on good and righteous things, those things that build up our godliness instead of tearing it down. Are you as confident as David was that when God tests your mind that He finds nothing there amiss?
The Lord examined David's heart at night and found nothing amiss. It is normally at night, when everything is quiet and dark, that Satan comes out and plays in our hearts. It is then that we are exposed to his accusations. It is then that he plants all kinds of sinful thoughts within us. Normally we are alert and aware of what he is doing during the daytime, but at night we tend to let down our guard. Do you have confidence that at the ending of day that you have lived in Christ in such a way that when the Lord examines your heart that nothing is amiss? Are you strong enough to resist Satan's attacks on your heart and mind in the night? If are not comfortable with what God knows about your thought life, you need to let the Lord change the way you think.
David was confident of his standing before God because he was determined to not sin in what he said. In order to accomplish that, we must be right with God in our heart, for out of the heart the mouth speaks. In order for us to say and do the right things, we must live rightly in Christ. We must keep our souls in good shape. We must not allow Satan access to it. It takes determination to ward off Satan. Are you careful about what comes out of your mouth? Think about what you say before you say it. Consider carefully whether your conversation is good or bad. If you know God is not pleased with what you say, then you need to get your heart right with God.