You can’t pay for a gift. You can only open it or leave it wrapped.

A gift stops being one the moment you pay for it. That is the awkward part of receiving anything freely: there is no way to square the account, and the discomfort pushes people into trying to earn what was already handed over. Only two options are available, opening it or leaving it wrapped. Neither of them involves paying.

Look at where you are trying to repay something given to you, whether by God or by a person who loves you. Try saying thank you and stopping there, which is harder than it sounds. Then use the thing, since an unopened gift honours nobody, least of all whoever gave it.