Alms were gifts of money to the needy. What Jesus said on this subject is applicable to all types of giving.
Interpreters have understood the practice of sounding a trumpet to announce alms-giving metaphorically and literally. Metaphorically it would mean that Jesus was using a figure of speech to picture showy giving something like "blowing your own horn."However, His description seems to have had a custom behind it. There is old evidence that during this period the Jewish priests blew trumpets in the Temple when they collected funds for some special need.301Alternatively, this may be a reference to the horn-shaped collection receptacles in the Temple that noisily announced contributions that people tossed into them.302However, Jesus mentioned the synagogues and streets, not the Temple. Probably Jesus referred to the blowing of trumpets in the streets that announced fasts that included alms-giving.303
The idea of not letting the left hand know what the right hand does pictures secrecy. The way to avoid hypocrisy is to let no other people know when we give. We can carry this to the extreme, of course. Jesus' point was that we should not draw attention to ourselves when we give. Hypocrisy does not just involve giving an impression that is incorrect, such as that one gives alms when he really does not. It also involves deceiving oneself even if one deceives no one else. A third kind of hypocrisy involves deceiving oneself and others into thinking that what one does is for a certain purpose when it is really for a different purpose. This seems to be the type of hypocrisy in view here.
"They were not giving, but buying. They wanted the praise of men, they paid for it."304
"The hypocrites are not identified here, but Matthew 23 clearly indicates that they are the scribes and Pharisees (Matthew 23:13, 14, 15, 23, 25, 27, 29). A clearer illustration of a facet of Matthew's style can hardly be found. First he intimates a fact, then he builds on it, and finally he establishes it. Here the intimation concerns the hypocrisy of the scribes and Pharisees."305
"As leaders,' the religious leaders evince their evilness most prominently by showing themselves to be hypocritical.' Hypocrisy in Matthew's story is the opposite of being perfect.' To be perfect is to be wholehearted, or single-hearted, in the devotion with which one serves God (5:48; Deut. 18:13). To be hypocritical is to be divided' in one's fealty to God. Hypocrisy, then, is a form of inner incongruity, to wit: paying honor to God with the lips while the heart is far from him (15:7-8); making pronouncements about what is right while not practicing them (23:3c); and appearing outwardly to be righteous while being inwardly full of lawlessness (23:28)."306
