One of the phrases that we recite several times in our Rosh Hashanah prayers is, "U’dbarcha Emet Ve’kayam La’ad" – "and Your word is true and endures forever." What exactly do we mean in this phrase, and why do we emphasize on Rosh Hashanah the point that Hashem’s "word" is true and eternal?
The commentators explain this phrase as referring to the comment of the Midrash (listen to audio recording for precise citation) that David Ha’melech said to the Almighty, "Master of the world! You can come upon us only with the attribute of mercy, for otherwise, we are unable to survive for even one moment!" David noted that if G-d judges us on the basis of the rules of strict justice, then nobody, not one person, will be given a favorable sentence. Furthermore, David made reference to the sin of Adam, which occurred on Rosh Hashanah (creation began on 25 Elul, and man was created on the seventh day, Rosh Hashanah; Adam committed his sin that same day). After the sin, G-d judged Adam mercifully, as otherwise he could not have continued living for another moment. And G-d at that point made a commitment that just as he showed Adam mercy and affection despite his wrongdoing, He would similarly judge all of Adam’s descendants with love and compassion every year on that day, Rosh Hashanah.
Thus, we declare in our prayers that G-d’s "word" – referring to His promise to Adam Ha’rishon – continues to be true and applicable, even to this day. For all time, we are guaranteed access to Hashem’s mercy and compassion if we utilize this day of Rosh Hashanah properly for prayer and repentance. This phrase, then, conveys a vital, comforting message to us all, assuring us that if we do what we are supposed to do on these days of Rosh Hashanah, Hashem will judge us mercifully and issue a favorable sentence.
