The Torah writes: "And you shall count for yourselves from the day following the [Passover] holiday, from the day that you bring the Omer [offering] that is raised, seven complete weeks there shall be until the day after the seventh week you shall count 50 days" (Leviticus 23:15-16).
These verses command us to count seven weeks from the time that the Omer — the new barley offering — was brought in the Temple — i.e. from the 16th of Nissan. We begin our count on the second night of Passover and continue until Shavuot, which is the 50th day after the offering. We actually counted 49 days, for our Sages had a tradition that the Torah’s use of the word "50" meant until the 50th day.
It is a mitzvah for each individual to count the days of the Omer by himself, for the Torah states: "And you shall count for yourselves." This mitzvah is applicable today, even though the Temple no longer stands and we no longer bring the Omer offering. Some maintain that the obligation today is rabbinic.
The correct time for counting the Omer is at the beginning of the night, for the verse states that we are to count seven complete weeks, and the count can be complete only if we commence when the 16th of Nissan begins. Since we commence counting the Omer at night, we continue to count at night throughout the entire 49 days.
If a person neglected to count one day, or if he counted the wrong number, he may no longer recite a blessing when he subsequently counts, but he must nevertheless continue to count.
The masters of Jewish mysticism see the 49 days [seven weeks] of the counting of the Omer as a period in which one can rectify the deficiencies which have marred the seven attributes upon which the temporal world is based. Our Sages, who delved into the deeper meanings of the Torah, teach that in the verse Genesis 1:31, the Torah is referring to the world thus rectified: "And the Lord saw all that He had done, and behold it was very good."
These seven attributes were replanted in the world — after the sin of Adam had made them deficient — by our great ancestors, "the Seven Shepherds." After they were reintroduced and strengthened, they remain in place even after sins that Israel has committed after the giving of the Torah. In every generation and in every time, whenever man chooses, he can come and cleave to the attributes of the Seven Shepherds, for the qualities that the implanted have internal strength.
The period during which the Omer is counted is most auspicious, for once Israel left Egypt and became a part of God’s portion, a gate of purity was opened for them — a gate that the people of their era entered and through which they became purified it over a period of 49 days. They rose from the status of brickmakers and straw gatherers serving the Pharaoh of Egypt, to become a people especially chosen by God, a nation of kohanim, kings, and ministers, all devoted to His service.
This path of purification was paved then, and each year when this period arrives, the gate is once again opened and the road made clear for all those who seek to assume the seven attributes in their completeness.
In the Zohar Chadash it is written:
"When Israel was in Egypt, they became defiled through all means of impurity until they sank to the 49th level of impurity. God brought them out of subservience to all these powers and led them to enter the 49th level of wisdom. This was not part of the original promise made to Abraham.
"We find that the Torah mentions the Exodus from Egypt 50 times, demonstrating God’s great kindness to Israel. When we count the Omer for 49 days from [after] the first day of the festival, it reminds us that on each day He brought Israel another step away from the defilement of Egypt — and led them to enter the gate of purity so that they would be worthy of receiving the Torah."
The Midrash (Vayikra Rabba 28) teaches that it was this [mitzvah of the Omer] that saved the Jews in the days of Haman, as Rabbi Levi taught:
When Mordechai saw Haman approaching him leading a horse, he said the himself: "It would appear to me that this wicked man is coming only to kill me." [Mordechai’s] students were seated before him and were studying. He told them: "Stand up and flee, lest you be burned in my fire!"
They replied: "Whether we be killed or live, we shall stand by you and not abandon you."
What did [Mordechai] do? He wrapped himself in a tallis and prayed while his students sat and studied.
Haman said to them: "What are you studying?"
They replied: "The mitzvah of the Omer that Israel would offer on this day in the Temple."
He told them: "This Omer, of what was it constituted — was it gold or silver?"
They replied: "It was barley."
He asked: "What was its value? Ten [valuable] kantarin?"
They answered: "Far less — ten ma’os."
Haman then said: "Arise [and have no fear], for your ten ma’os have overcome my 10,000 bricks of silver [that I had pledged to the treasury for the right to annihilate the Jews]."
Reprinted with permission from InnerNet Magazine