One way I like to picture God’s holiness is as strong radiation. His holiness constantly is radiating out from him. By its very nature, it destroys anything imperfect with which it comes into contact.
This is why, in order to enter God’s presence, we can’t have the slightest imperfection. Otherwise we will be destroyed. But how can we do that? By being clothed in Christ’s righteousness. “he has clothed me with garments of salvation and arrayed me in a robe of his righteousness” (Isaiah 61:10). Or, in keeping with the illustration, by wearing the radiation suit made by and given by Jesus.
Suppose, however, that Jesus has given me his radiation suit, but I had been working hard on making my own. I realize Jesus’ suit is vastly superior so I put it on. But I have worked so hard on my own suit that I decide to use just one of its gloves. So, I substitute the glove I made for the one Jesus supplied. I walk into God’s presence only to be destroyed by his holiness. My glove couldn’t protect me from the radiation of his holiness because it wasn’t perfect – it was flawed. “For whoever keeps the whole law and yet stumbles at just one point is guilty of breaking all of it” (James 2:10).
The point is that no matter how little we rely on ourselves – maybe I just replace one finger on one glove – any little bit of reliance on self becomes a fatal flaw. Even the tiniest flaw in a radiation suit spells disaster. Neither does it matter what my motivation is for slightly relying on myself. It could be prideful reluctance to give up what I worked so hard doing – it could be the thought that this is what God wants. It doesn’t matter – if we rely, even ever so slightly, on what we have to do in order to stand in God’s presence, we have a flawed radiation suit – and we will be destroyed.
Since we sin so much, our obedience isn’t perfect. Therefore, the only thing our imperfect obedience does is make our suit flawed. And a flawed suit is a formula for disaster. Whatever you do, don’t try to add to Jesus’ perfection!