Remember all thy offerings, and accept thy burnt sacrifice; Selah. Remember all thy offerings - The minchah, which is here mentioned, was a gratitude-offering. It is rarely used to signify a bloody sacrifice.
Burnt sacrifice - The olah here mentioned was a bloody sacrifice. The blood of the victim was spilt at the altar, and the flesh consumed. One of these offerings implied a consciousness of sin in the offerer; and this sacrifice he brought as an atonement: the other implied a sense of mercies already received, and was offered in the way of gratitude.
David presents himself before the Lord with offerings of both kinds.
This prayer of the people is concluded with Selah, which we have taken up in the general sense of so be it. Hear and answer. It will and must be so, etc.