The first Shabbos in the new year is traditionally known as Shabbos Shuva. As this Shabbos occurs during the Ten Days of Repentance, the Haftora read, which begins "Shuva Yisroel," "Return Israel," concerns repentance. Additionally, there is a custom that the Rabbi of each synagogue gives a special congregational lecture on this Shabbos on the topic of repentance and preparation for Yom Kippur. The Sfas Emes writes that one should strengthen their observance of mitzvos and performance of good deeds specifically on this Shabbos. He quotes the Talmud (Shabbos 118b) "Rab Judah said in Rab's name: Had Israel kept the first Sabbath, no nation or tongue would have enjoyed dominion over them, for it is said, (Shmos 16:27) 'And it came to pass on the seventh day, that there went out some of the people to gather' which is followed by, (Shmos 17:8) 'Then came Amalek.'"

Before the first Shabbos the Jewish nation spent in the desert after their departure from Egypt, Moshe informed them that Manna would not fall on Shabbos. Instead, double portions would fall on Friday, and the extra portion would be for use on Shabbos. However, two people conspired to undermine this command that Moshe gave to the people. Early on Shabbos, they went and scattered manna they had collected from the day before, in violation of the laws of Shabbos and G-d's command. They hoped that the people, upon arising and going outdoors, would see the manna and feel that Moshe's instructions were wrong. Birds thwarted the plot by eating the manna before anyone saw it. However, on this very first Shabbos, people desecrated the day's sanctity. Because the nation of Israel in its entirety did not observe the first Shabbos, the Talmud says, they were soon subject to attack by Amalek and many other nations since.

The Sfas Emes explains that we have an opportunity to rectify this situation. If we observe the first Shabbos of the year properly, we can assure that the nation of Israel will not suffer at the hand of another nation this year. We, together, by protecting the sanctity of Shabbos, by spending the day engaged in spiritual pursuits, can bring great good to all. We can undo that oppression which was brought upon us in the days of our ancestors. All it requires is just one Shabbos, and that Shabbos is Shabbos Shuva.