What an amazing thing, the Torah is. We have the Written Torah - the 5 Books of Moses, which start with the "stories" of the creation and the forefathers, Avraham Yitzchak, and Yakov, through the exile of the House of Yakov in Egypt, the redemption, Giving of the Torah, and building of the Mishkan.
At this point begins the messages between G-d, through Moshe Rabeinu, to the Nation of Israel. The laws of the sacrificial service and the laws of the kohanim, the laws of kashrut, maasrot (tithes), agricultural laws, the laws of the holidays, etc. 613 commandments (mitzvot) in all, 248 positive commandments of things we have to do, and 265 negative commandments of things we are do specifically not do.
These commandments define what it means to be a Jew. In modern terms, an "orthodox Jew", or I guess if someone tries his best to keep as many of the commandments as possible he is an "ultra-orthodox Jew". But these commandments, and the study of the Torah that contains these commandments, is what it means to be a Jew.
Now, the Torah is basically composed of a mix of "stories" together with specific commandments from G-d to Israel, through Moshe Rabeinu.
The prophecy that revealed both the very precise text of the Torah, along with the specific commandments (and their oral detailed explanation, which became the basis for the Oral Law), unlike with other prophecy, was preceded by the open revelation of G-d to every single member of the Nation of Israel, man, woman, or child. This was preceded by the great miracles of the redemption from Egypt, all for the purpose of the Giving of the Torah - the marital union between G-d and the Nation of Israel, fulfilling the culmination of creation which started in Bereshis (In the Beginning G-d created the heaven and the earth.)
Our sages teach that the Giving of the Torah was actually not yet the marriage, but rather the betrothal, the culmination of the marriage will be in the Coming of Moshiach, immediately now, Amen.
Kabbalah explains that the Torah is nothing less the G-d's Will and Wisdom (the sefirot of Keter and Chochmah Ila'ah). Indeed, the details of how these levels become vessels of G-d's Infinite Light is the subject of much of the wisdom of Kabbalah, however once this takes place, a channel is formed between the Infinite Creator and Finite Creation. This is why the Torah begins with the "stories" of creation, first there was the Torah, but the Torah exists on a level before (beyond) creation, therefore "in the beginning", the beginning of creation, G-d created the spiritual and the physical, so that within the physical there will come to be a Nation of Israel which will receive the Torah and fulfill it physically and materially within creation, thus becoming G-d's "Bride" - His means of manifesting physically within his creation, fulfilling His divine Will and Wisdom.