This is the first of a number of psalms (eighteen) to which titles are prefaced which connect them with David, eight out of the number having historic references. There is a remarkable fitness in every case between the incident thus indicated and the psalm following; but whether the placing is accurate or not is open to question.
This is indeed one of the great penitential psalms, being the fourth in the seven which are usually so described. It opens with a general cry for pardon that comes out of a deep sense of sin and an equally profound desire for forgiveness. In the first three verses sin is described as "transgression,” "iniquity:" "sin"; and the mercy sought is to 'blot out," "wash," "cleanse." The penitent soul cried for forgiveness on the basis of confession. Suddenly the intensity of conviction deepens as the act of sin is traced back to its reason in the pollution of the nature. This leads to a deeper cry. As the first was for pardon, the second is for purity, for cleansing of heart, and renewal of spirit.
The prayer goes on to seek for the things which follow such cleansing, maintenance of fellowship, and consciousness of joy. Looking on in hope, the song anticipates that service of thanksgiving and praise which will issue from such pardon and purity.