Matthew 6
The Sermon's second major movement addresses the three core practices of Jewish piety — giving, prayer, and fasting — with the recurring diagnosis: do not do these things to be seen by people. Each practice is reshaped around the audience of one: the Father who sees in secret rewards in secret, in contrast to the hypocrites who perform for human approval and receive exactly the reward they seek — human attention, nothing more. The Lord's Prayer is embedded in the prayer section as the model: Father, hallowed name, kingdom coming, will done on earth as in heaven, daily bread, forgiveness given and received, deliverance from the evil one. The chapter concludes with the teaching on anxiety and possessions: no one can serve God and money; the eye (single, generous, or divided, stingy) determines whether the whole body is full of light or darkness; and the birds of the air and lilies of the field make the argument that the Father who clothes the grass will certainly clothe his children. Seek first his kingdom and righteousness, and all these things will be added.
Matthew 6:1
Beware of practicing your righteousness before other people in order to be seen by them, for then you will have no reward from your Father who is in heaven. Chapter 6 turns from the content of kingdom righteousness (chapter 5's antitheses) to the motive from which it is practiced. The same actions — giving, praying, fasting — can be performed either for the audience of the Father or for the audience of other people. The beware communicates that the danger is not obvious: the acts themselves are identical; the difference is entirely internal. John 12:43 describes people who loved the glory that comes from man more than the glory that comes from God — the human-approval motive infects the whole range of religious practice without the external observer being able to detect it.
Matthew 6:2
Thus, when you give to the needy, sound no trumpet before you, as the hypocrites do in the synagogues and in the streets, that they may be praised by others. Truly, I say to you, they have received their reward. The hypocrites — the Greek word means actors performing a role — give in a way that ensures their giving is visible and praised. The sounding of a trumpet before giving to the poor may be literal (some scholars think it refers to trumpet-shaped collection containers in the temple) or figurative. Either way, the giving is designed for maximum visibility. They have received their reward communicates that human praise is a real reward — they got what they were seeking. But it is the only reward they will receive; the Father's reward, which is what the disciple community seeks, has been forfeited.
Matthew 6:3
But when you give to the needy, do not let your left hand know what your right hand is doing. The positive instruction is the most radical alternative to public giving: the anonymity so complete that even the giver's own self-awareness is minimized. The left-hand and right-hand language is hyperbole for the internalization of generosity — the giving that does not congratulate itself or keep score of its own record. This is the generosity described in Romans 12:8 as giving with simplicity (or generosity without ulterior motive). The discipline of secret giving trains the practitioner away from the self-congratulation that public giving enables and toward the genuine other-orientation that kingdom giving requires.