We have transgressed, we have acted perfidiously...
Why does one strike his chest over his heart with his hand when reciting the confession?
According to Torah law, one cannot be found guilty lest there are witnesses who testify to the crime. In the prayer of “Let us proclaim the mighty holiness of this day” -- we proclaim, “You open the Book of Remembrance and it reads itself; every man’s signature is in it.” Thus, by applying his signature to all his deeds, the person serves as the witness who attests to the validity of his actions.
The Torah prescribes that when punishment is meted out, “The hand of the witnesses shall be upon him first to put him to death.”1 Thus, in keeping with this rule, the hand -- which is the witness -- is, so to speak, the first to apply punishment. It strikes the heart because it is the power in the body that, through expressing its desires, causes man to sin.
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Rabbi Yisroel Meir of Radin, the Chofetz Chaim, once said, “It is not the one who knocks on his heart for his sins that G-d forgives; rather it is the one whose heart pounds him for the sins he committed.”
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Why is it customary to start each verse in this prayer with a lyrical melody -- wouldn’t it be more appropriate to cry and wail?
The Talmud2 states that when one’s repentance is motivated by fear, his willful transgressions are accounted for the the penitent as inadvertent errors. When one’s repentance is motivated by love, his willful transgressions are accounted for him as merits. Hence, we are in a confident spirit when we make our confession and repent because of the many merits being acquired.3