स तया श्रद्धया युक्तस्तस्याराधनमीहते। लभते च ततः कामान्मयैव विहितान् हि तान् ॥

sa tayā śhraddhayā yuktas tasyārādhanam īhate labhate cha tataḥ kāmān mayaiva vihitān hi tān

He endowed with that faith, seeketh the worship of such a one, and from him he obtaineth his desires, I verily decreeing the benefits;

In plain words: With that faith, the person worships that god and gets what they wish for. But Krishna says he is the one who really grants those gifts.