See Psalm 41:4
Most of us go through life in a semi-conscious state of spiritual blindness. If we prosper, we attribute success to our own abilities and think no more about it. Or if we are troubled with difficulties and problems, we attribute it to bad luck or bad circumstances or to someone else.
But the psalmist says something fundamentally different. He says, “I have sinned against God.” As a result, he is sick and cannot cure himself. His conscience is stricken, and he can only plead for mercy.
In Biblical Psychology, Oswald Chambers writes, “Conscience is the innate law in nature whereby man knows he is known.” When we come to that place where we know that we are known by God, then the true state of our unhealthiness is placed in stark contrast to the holiness of God. We recognize, perhaps for the first time, that we are not as good as we think we are. In fact, this realization can come as an awful shock, but God is truly merciful and He provides, through Jesus Christ and the Holy Spirit, a way for us not only to ask for mercy but to receive it: “Ask and it will be given to you; seek and you will find; knock and the door will be opened to you. For everyone who asks receives; he who seeks finds; and to him who knocks, the door will be opened” (Matthew 7:7–8).
–Eric Kampmann, Signposts