Muhammad Asad:Translation:
For, only this prevents their spending from being accepted from them: 77 they are bent on refusing to acknowledge God and His Apostle, and never pray without reluctance , 78 and never spend [on righteous causes] without resentment.
77 Lit., "nothing prevents their spending from being accepted from them except that. ..", etc.
78 Lit., "and they do not approach prayer without being reluctant" -i.e., when they participate in acts of worship they do it only for the sake of outward conformity, and not out of inner conviction.