Question:

Why is it important to have a large family, and how is this connected to Redemption?

Answer:

Each child born is a world unto him or herself!

The mitzvah of pru u'rvu, "be fruitful and multiply," is one of the means by which we hasten the Redemption. It is written in Yefeh Toar, a commentary of the Midrash: "Through being fruitful, we hasten the Redemption, as is written in the Talmud, that the son of David will not come until all the souls in the storehouse in heaven called "Guf" will descend into bodies. Therefore, one who does not engage in procreation holds back the Redemption."

It is also important to note the expression of Maimonides with regard to the birth of children: "One who adds even one soul to the Jewish people is as if he has built an entire world!"

Even though the Torah commandment of being fruitful and multiplying can be fulfilled through having just one son and one daughter, nevertheless there is a mitzvah to continue procreating beyond the minimum, since the purpose of this mitzvah is to settle and build the world, and each child born is a world unto him or herself!

The Lubavitcher Rebbe adds that in addition to bearing physical children, the mitzvah of pru u'rvu is fulfilled spiritually, by embracing our fellow Jews and encouraging them to follow the path of Torah and mitzvot. Through drawing a fellow Jew closer to Torah, one brings the world to its perfection. Then the prophecy will be fulfilled: "The glory of G-d will be revealed and all flesh together will see that the name of G-d has spoken," with the true and complete Redemption, may it happen immediately.