This is the last Shabbat of the month of Elul, the last month of the year. The last Shabbat of each month is called Shabbat Mevarchim, during which we recite a special blessing so that the coming month will bring good things, joy, and peace.
However, this Shabbat, we will not recite that blessing. HaShem Himself blesses the month of Tishrei, and His blessing gives us the strength to bless the remaining eleven months of the coming year.
What is the blessing that God gives? All of you are standing here today.
What does "today" mean? When is today? Every day? Any day? Our sages tell us that the Torah is speaking of Rosh Hashanah, when we stand before HaShem in judgment.
Can you imagine what people look like when they're in court being judged? When the judge declares someone guilty, they sit huddled in their seat, with a pained expression and their head bowed. Conversely, when the judge declares someone innocent, they stand tall, head held high, face beaming with joy. The Torah tells us, "All of you are standing today." On Rosh Hashanah, as we all pass before God to be judged, we are blessed to stand firm as the verdict is announced.
The Torah also says, "all." When God sees the Jewish people coming together, it is like a father seeing all his children playing happily together. Nothing can make him happier. When God sees us coming together in mutual love, He blesses us with a ktivah vechatimah tovah, that we may be inscribed and sealed for good, for a good and sweet year.
Extracted from Please tell me what the Rebbe says.