heart's desire. Compare Psalms 20:4; Psalms 37:4.
Selah. See App-66. Here connecting the reason (Psalms 21:3) of the answer (Psalms 21:2) with the prayer of Psalms 20:4. which, by the Selah of Psalms 20:3, had been connected with the reason given there: i.e. atonement.