so that your merciful deeds may be in secret, then your Father who sees in secret will reward you openly.
That thine alms may be in secret,.... May be done in secret, and be kept a secret. The allusion seems to be to the secret chamber, where money was brought privately for the relief of the poor. "There were two chambers in the sanctuary, the one was , "the chamber of secrets", and the other the chamber of vessels: the chamber of secrets was that...
Hypocrisy is a subtle sin that steals into our alms unawares, and it is ruinous if it takes hold. Do good from an inward, vital principle approved by God, not to be applauded by men; vain-glory is the dead fly that spoils the whole box of precious ointment.
AI summary
Commenting on Matthew 6:1-4
That thine alms may be in secret, and thy Father which seeth in secret himself shall reward thee openly--The word "Himself" appears to be an unauthorized addition to the text, which the sense no doubt suggested. (See Ti1 5:25; Rom 2:16; Co1 4:5). Prayer (Mat 6:5-6).