Purge me with hyssop, and I shall be clean;
wash me, and I shall be whiter than snow.
Let me hear joy and gladness;
let the bones that you have broken rejoice.” (Psalm 51:7–8)
Some argue that religion is simply a philosophical affair. It’s to do with abstract theories and arguments about things that don’t really matter. It doesn't have much to do with everyday life and, should be simply a private matter. You know the arguments.
These verses from the lips of David give the lie to all this. The king’s sense of his guilt is overwhelming, a pain he likens to broken bones. This is no abstract philosophy, this in overwhelming angst. Those who have felt a similar emotion know that it is all encompassing, and all consuming.
In the midst of this, David does the only thing he can: he cries out for mercy, for cleansing. This is, he knows, something which is beyond him. If he has sinned against God, then only God can forgive. This he longs for, but also more. He longs to be purified so that he can once more experience joy and gladness.
It is to these deepest levels of human nature that Christianity speaks. It is not abstract. It is deeply real.