In 2 Samuel 6, there is a story about a man named Uzzah. He was helping move the ark of the covenant back to Jerusalem. It was important because the ark was the sign of God's presence among the Israelites. It was a very joyous occasion because they were bringing it home in a sense.
There were a lot of strict rules about the ark. They were supposed to carry it on poles and not touch it. When they finally went to bring it home, a man named Uzzah reached out to touch it. Not because he wanted to break the rules, but to steady it from falling off the cart. He was trying to save it. And how did God respond? He struck him dead. Just like that. Just for putting his hand out to prevent this precious symbol from crashing to the ground.
"When they came to the threshing floor of Nacon, Uzzah reached out and took hold of the ark of God, because the oxen stumbled. The Lord's anger burned against Uzzah because of his irreverent act; therefore God struck him down and he died there beside the ark of God."
2 Samuel 6:6-7
After that David gets mad.
"Then David was angry because the Lord's wrath had broken out against Uzzah, and to this day that place is called Perez Uzzah (which means outbreak against Uzzah). David was afraid of the Lord that day and said, "How can the ark of the Lord ever come to me?" 2 Samuel 6:9-10
And it's true. Who can stand in the presence of God? No one. But in all my Christianness, in all my bible verse t-shirts, in all my "goodness", I have thought that I can. How could God not think I'm great? How could God be displeased with my mistakes? It's not as bad as what some people are doing.
God cannot look at me. I am a dirty, rotten, filthy sinner. We all are. If you are not a sinner, then you have no need for Jesus.
"When they sin against you - for there is no one who does not sin - " 1 Kings 8:46
But you know, it's not as bad as you might think to be shown that. There is freedom in seeing that my only chance is Jesus' sacrifice for me. He died for my sins. He took the punishment that I deserve.
And because of that, I can stand before Him. Not because of me, not because I teach Sunday school; but because of Him.
"But who can endure the day of his coming? Who can stand when he appears? For he will be like a refiner's fire or a launderer's soap." Malachi 3:2