Matthew 6:3

3Youσοῦhoweverδὲdoingποιοῦντοςcharityἐλεημοσύνηνnotμὴlet knowγνώτωtheἡleft [hand]ἀριστεράof youσουwhatτίis doingποιεῖtheἡright handδεξιάof youσου,

But [in] your doing charity, do not let your left [hand] know what your right hand is doing,