But when you give alms, do not let your left hand know what your right hand is doing, so that your alms may be done in secret; and your Father who sees in secret will reward you.
Matthew 6:3-4
Don't prooftext. If you and your treasurer are the only people who know that you are giving money to your church, the spirit of Mat. 6:3-4 is still fulfilled. The abuse which Mat. 6:3-4 is aimed at is people who give money ostentatiously, not those who do so quietly with a check.