God gave us the right to give to Him. Government has no business interfering in our relationship with Him. Therefore, offerings to a religion are part of exercise of religion.
So far as the individual’s income, let’s get rid of the income tax, repeal the 16th, and go to straight sales tax. Then deductions won’t matter.
Heck, I'd be fine with a flat-rate income-tax — no deductions, no credits, no exemptions, no exceptions,