Psalm 32 begins, as 119, with a double-barrelled blessing. Part of that blessing is the blessing of covered sin (32:1) which is only possible if we do not cover up our sin ourselves (32:5). it is only possible when we confess our sin (32:5).
The irony of not confessing sin, that is trying to cover it up and hoping it won’t be notices, is that it is ever before me, and before God. No matter how hard I may try to bury it in my own mind, it is like a cork. However many times I try to sink it, it floats! “My sin is ever before me” (Psalm 51:3).
The sin of Achan (Jos 7) illustrates the folly of trying to cover our sin. However well Achan hid his sinful deed from other people, God himself saw it. How true it is: “whoever conceals his transgressions will not prosper, but he who confesses and forsakes them will obtain mercy.” (Pr 28:13)
Confessed sin is covered sin. And not only is it covered, but it is taken away “as far as the east is from the west” (Psalm 103:12). When God covers sin he removes all trace of it. That is the essence of forgiveness — taking away. These two ideas are also linked in Ps 85:2. God has done this by his Son, as John the Baptizer declared, “Behold, the Lamb of God, who takes away the sin of the world.” (Jn 1:29) Indeed, it was the very reason Christ came, “You know, he appeared to take away sins.” (1Jn 3:5)