“Holy, holy, holy is the LORD Almighty; the whole earth is full of his glory.” Is 6:3
The bible tells us God is holy. He is holy in that he is pure and set apart from his creation. He cannot look upon sin. Even the sinless seraphim cover their faces and cry out “Holy, holy, holy”. How much more as sinful beings should God’s holiness be apparent to us?
If we are Christians, we should also be holy.
But just as he who called you is holy, so be holy in all you do; for it is written: “Be holy, because I am holy.” 1 Pe 1:15-16
Whilst we may not be perfect in this life, we should strive to be. Not that we could in any way justify ourselves, but because God’s Holy Spirit lives in us and works in us, making us holy.