Psalms 139 emphasizes the omniscience of God.  His knowledge is unsearchable, and it includes knowing all about every one of us.  

Psalm 139:1-3 (ESV)
¹  O LORD, you have searched me and known me! ²  You know when I sit down and when I rise up; you discern my thoughts from afar. ³  You search out my path and my lying down and are acquainted with all my ways.

The writer of Hebrews recognized this in one of the great passages that speak of the boundless knowledge of God.

Hebrews 4:13 (ESV)
¹³  And no creature is hidden from his sight, but all are naked and exposed to the eyes of him to whom we must give account.

This is one of a plethora of passages that speak of God being thoroughly acquainted with us.  In Job 34:21, Elihu said, “For His eyes on are the way, of a man, and He sees all of His steps.”  The Psalmist wrote, “The Lord looks down from heaven; he sees all the children of men.”

God does not just see some people, He sees all people.  The uniqueness of Hebrews 4:13 is that it goes beyond man and includes every creature.  Have you ever really thought about that?  God knows, not only everything that we do, but everything that every animal, insect, and microscopic organism does as well.  No creature is hidden from His sight.

In Psalms 139, David focused on himself, which is what we should all do.  God searches and knows every one of us just like he did David.  He knows every time we sit down and get back up.  He knows our thoughts before we even think of them.  We should say with David, “Such knowledge is too wonderful for me.”

Knowing that God knows every little detail about our ways should have a profound effect on our lives.  It should influence the way we live every day.  It is not like God takes time off and is unacquainted with us at times.  God sees us every new day.  He knows where we go and how we behave when we get there.

Some brethren act differently during the week than they do on Sunday.  It is as if they think they are in the presence of God on the Lord’s day, but somehow escape His notice every other day.  David reminds us that such is not the case.  Since God is the One Who will judge us in the end, and since He knows everything that we do, we should live our lives with godly fear.

1 Peter 1:17 (ESV)
¹⁷  And if you call on him as Father who judges impartially according to each one’s deeds, conduct yourselves with fear throughout the time of your exile,

We should even be careful of our words and thoughts.  Too many think that as long as we avoid committing major, overt acts of sin, our words and thoughts do not matter very much.  Jesus, however, warns us that every careless word will be judged by God (Matthew 12:36);  and, Paul reminds us that what we think about is very important (Philippians 4:8).

God is the great searcher of men, and nothing we do ever escapes His eyes.  Allow this truth to influence you every day.

As you wind down for the night, think about these things.