Psalms 32:2

Psalms 32:2. Blessed is the man unto whom the LORD imputeth not iniquity, and in whose spirit there is no guile

He has no need to dissemble now, for his sin is forgiven. David had tried to tamper with his conscience after his great sin. He invented all sorts of excuses and schemes, to try to hide his guilt, but when, at last, he was fully convinced of the awful sinfulness of his sin, and when God had put it away for ever, then, when the guilt was gone, the guile went, too.