The midrash asks: Why does the Torah start with creation, and not with the first mitzvah? (See Rashi for the answer.) We learn from this question that the Torah is not a storybook, but is primarily a book of laws.

In this vein, Rav Yosef Dov Soloveitchik z"l writes: When the Torah tells us the story of creation, its intention is not to reveal metaphysical secrets but to teach us a practical law. The description of creation is a legal text, in which are to be found everlasting halachic principles, just like in Parashat Kedoshim or Parashat Mishpatim. If the Torah chose to relate the tale of creation to man, we may clearly derive a law from it, specifically, that man is expected to engage in creation.

When G-d created the world, He left room for man to exercise his creativity. Man is responsible for "fashioning, engraving, attaching and creating" (to borrow the language of the Sefer Yetzirah--a midrash attributed to Avraham Avinu).

When one recites the verse from our parashah in the Friday night kiddush, "And the heaven and the earth were finished and all the host of them," he testifies not only to the existence of a Creator, but also to man's obligation to become a partner with the Almighty in the continuation and perfection of His creation. (Ish Hahalachah)

This parashah has one mitzvah, i.e., the commandment to be fruitful and multiply, as it is written (1:28), "And G-d blessed them, and He said to them, 'Peru u-revu' / 'be fruitful and multiply'." Among the reasons for this mitzvah is that G-d created the world that it should be inhabited. This is a great mitzvah, as a result of which it is possible for all the other commandments to be performed.
(Sefer Hachinuch No. 1)

When the Jews were sent into exile, Hashem sent the prophet Yirmiyah to tell them, "Take wives and bear sons and daughters." He meant: Do not say, since we are in exile, why should we multiply?
(Aruch Hashulchan, Even Ha'ezer 1:1)

The mitzvah is fulfilled by bearing one son and one daughter.
(Shulchan Aruch, , Even Ha'ezer 1:5)

Some say that the mitzvah is fulfilled when one has done his part towards having children. Whether or not a child is conceived is in G-d's hands. Indeed, this is true of all mitzvot--for example, man has no control over whether he has money to give to charity or whether he has a house on which to put a mezuzah.

Our sages listed nine different qualities of oil, and taught that all nine may be brought on the altar. Asks Rambam: Then why recognize different levels at all? So that someone who wants to be meritorious will subdue his yetzer hara and open his hands and bring his korban from the highest quality ingredients, as the Torah says (4:4), "And as for Hevel, he brought from the firstlings of his flock and from their choicest, and G-d turned to Hevel and to his offering." So everything that one does for the honor of G-d should be from the best--if one builds a shul, it should be nicer than his house. If one feeds the poor, he should feed them the best food on the table, and so on.
(Hil. Isurei Mizbeach 7:11)

Yet Adam did not die! Rav Yosef Yoizel Horowitz (the "Alter" of Novardok) z"l explains that this verse is not a threat of punishment, but a prediction: If you eat from the Tree of Knowledge, you will become too smart for your own good. Chazal explain that by eating from the Tree, Adam made the yetzer hara a part of himself. While Adam wanted this new challenge of facing off against the yetzer hara, Hashem predicted that man would fail. "You shall surely die."
(Madregat Ha'adam)

Rav Chaim Friedlander z"l writes: The yetzer hara sits at the door and anticipates the door's being opened a tiny crack. The yetzer hara cannot break down the door. It cannot entice man unless man opens the door and invites it in. Man's role is to rule over the yetzer hara--to keep the door closed and the yetzer hara outside. (Siftei Chaim: Elul)

From the humor of our sages......

As a child, the future Rebbe Eliezer of Dzikov was reprimanded by his father, Rav Naftali of Ropshitz for some naughty act. "But what can I do if my yetzer hara entices me?" the child asked.

"Learn from your yetzer hara," the father said. "Look how faithfully he performs his task."

"True," said the child, "but the yetzer hara has no yetzer hara to distract him."

A descendant of the Chatam Sofer and of Rabbi Akiva Eiger, Rav Glasner was a great scholar in his own right. His older contemporary, Rav Eliezer Dovid Gruenwald, addresses him in a letter: "The rabbi, the great light, wise and expert in the halls of Torah, pure thinking with the best type of intellect, crowned with good conduct, the complete wise man, a sapphire and diamond." (Dor Dorim p.235)

Rav Glasner succeeded his father, Rav Moshe Shmuel Glasner, as Chief Rabbi of Klausenberg, Rumania, in 1922, and served there until the deportation of the Jews in 1944. (A biography of the older Rav Glasner appeared in Hamaayan two years ago this week.) He was deported to Bergen-Belsen, but was saved from there on the famous "Kasztner train." (Rudolf Kasztner was a non-religious Hungarian Zionist who struck a deal with Adolf Eichman ym"s to save some 1,700 Jews in exchange for trucks. Years later, an Orthodox Israeli journalist accused Kasztner of acting improperly, and Kasztner sued for libel. After a celebrated trial, Kasztner lost. He was exonerated on appeal, but only posthumously, having been murdered in 1957. Ironically, the most famous person saved by Kasztner was Rav Yoel Teitelbaum, the Satmar Rebbe zt"l.)

After the War, Rav Glasner lived in Zurich until his death at age 71. His works include: Dor Dorim and Ikvei Hatzon in Hebrew, and a work in German. Rav Glasner writes in Ikvei Hatzon that at the end of the six days of creation, the world was complete only in a physical sense. The true completion of creation was on the day when the Torah was given. Therefore it says (Bereishit 2:2), "And G-d completed on the seventh day His work which He made"--a reference to the giving of the Torah, which occurred on Shabbat. In this vein, Rav Glasner explains Chazal's teaching that the first two millenia of history are called "Tohu va'vohu"/"chaos." The Tohu va'vohu which reigned at the beginning of creation was not fully eradicated until the giving of the Torah approximately 2,000 later. (In this context, Chazal call "the giving of the Torah" when Avraham began observing it.)