Psalm 139 has David talking about how God sees everything he does (sitting, standing, laying, speaking!) and even knows his motives. This is exactly what omniscience means (“Omni” being “all” and “science” being “knowledge”); God has all knowledge. There are two things we can take away from the fact that God knows everything.

1. We can take comfort in the fact that God can see us and is with us anywhere and everywhere we might go. He can always lead us and guide us.
2. We can take caution in the fact that God knows all our sins. There is nothing hidden from us. He watched us commit them!
3. God knows how many days you have left, and when your last day on this earth is.

So then, in terms of definition omniscience means all-knowing… but in terms of implication it means that God cannot be fooled, He knows literally everything. Everything we have ever done and will ever do. And what does that mean? Look at David’s request toward the end of the Psalm. David asks God to help him avoid becoming an enemy of the Lord. We should do the same. Sin can lead any of us astray. And God knows that, He knows where we are weak, and He knows where we are being attacked, and He WANTS to help us, but He is not going to go against our will to do so.

If God already knows our failings, let’s embrace that all-knowing-ness and ask him to help us deal with them.