Rabbi Moshe Rivkash was an older contemporary of the ShaCh (Rabbi Shabse Cohen and, like him, a native of Wilno. Both of them became famous for their commentaries on the Shulchan Aruch. Rabbi Moshe Rivkash was the author of Be'er Hagolah, a commentary on the Shulchan Aruch, including citations of the Talmudic and Halachic origins of the laws.

Rabbi Moshe was born in a -well-to-do family. His father's name was Naftoli Hirsh Sofer. Because of his great piety, Rabbi Moshe was given the title "Chosid."

He was caught in the great catastrophe which overtook the Jewish community of Wilno on the 24th of Tammuz, in the year 5415, in the wake of the Chmielnicki uprising known as the calamity of 5408 (Gzeras TaCh) which lasted for ten years. That Thursday, 24th of Tammuz, Wilno was invaded by hordes of Tartars and Cossacks, part of Chmielnicki's defeated and scattered army. They sacked the flourishing Jewish community of Wilno; they massacred 25,000 peaceful inhabitants of the city, and set the city on fire. The fire burned for seventeen days and left the city in a shambles.

Many Jews, anticipating this invasion, bad succeeded in making their escape, just in time. Providing themselves with horses and carts, these more fortunate Jews fled with their wives and children, and whatever possessions they could take with them. Others fled on foot and sought refuge in the woods surrounding the city, carrying their infants in their arms.

Rabbi Moshe Rivkash managed to send off his wife and children a day ahead, while he fled on foot the following day. Among the other famous refugees from Wilno on that day were the above-mentioned ShaCh, also Rabbi Ephraim Cohen (author of Sh'ar Ephraim), Rabbi Aaron Shinuel Kaidanover (author of Birkas Hazevach) and many other outstanding scholars.

In the introduction to his book, Rabbi Moshe Rivkash describes the terrors of that experience. "I fled from Wilno with nothing but my walking staff in my right band, and my Tefillin bag in my left," he writes, lamenting the loss of his house full of everything good, and, above all, his treasured library, which he had inherited from his father, and which he had enlarged by his own new acquisitions. Among his sacred books were many Talmudic tractates, upon which he had written marginal notes and comments, the fruits of many years of intensive Talmudic study.

He wandered with the other refugees through the province of Zamut, coming close to the borders of Prussia. The plight of the refugees was more than they could endure. They were further victimized by invading Swedish troops and lost whatever possessions they had.

Finally Rabbi Moshe and part of his family, with some other refugees, managed to get on a boat sailing for Amsterdam. Here they were met with great compassion by their Sephardic Jewish brethren, who clothed them and fed them. Other ship-loads of refugees which continued to arrive in Amsterdam were similarly cared for. The arrival of these refugees created a shortage of dwellings in Amsterdam, and prices of food and clothing sky-rocketted. The good people of the Amsterdam Jewish community therefore secured transportation for many refugees to go on to Frankfort, where they were cared for by the Jewish cornmunity of that city.

Rabbi Moshe, however, was kept in Amsterdam, where the leading Rabbis, Rabbi Shaul Halevi Murtira and Rabbi Yitzchak Abuhav, and some prominent lay members of this community, considered it a privilege to support Rabbi Moshe Rivkash and his family. With their financial support, Rabbi Moshe undertook the task of preparing a new publication of the Shulchan Aruch, together with his commentaries. Thus it was here that the Shulchan Aruch was published with the commentary Be'er Hagolab ("Fountain of the Exile"), on all four sections of the Shulchan Aruch. It was first published in the year 5421 (1661), and again in the year 5424 (1664).

Later, when peace was restored in his native land, Rabbi Moshe returned to Wilno. Here his soul returned to heaven at the end of the year 5431, or beginning of 5432 (1672). His Tzavoah (last will and testament) was dated 13th of Tammuz, 543 1.

Rabbi Moshe Rivkash left a substantial amount of his estate in trust for the support of charitable institutions. The income from this trust continued to be distributed for Tzedoko by his descendants down to most recent times.

Rabbi Moshe Rivkash also wrote other works on Halachah and commentaries on the Mishnah and Talmud, which, however, he was not able to complete. In his last Will he expressed the hope that his sons Rabbi Pesachiah and Rabbi Joseph might be able to complete them and prepare them for publication. Unfortunately, this hope apparently did not materialize.