תהילים כ:ד פירוש: רש״י

your meal offerings...burnt offerings They are the prayers that you pray in battle.

fat Heb. ידשנה, an expression of fat, as (in Deut. 31:20): “and it will eat and be satisfied, and it will become obese (ודשן),” i.e., He will accept them [the prayers] willingly like fat burnt offering.