Three passages in different parts of Tanach dovetail to reveal a fascinating historical incident that explains our custom of taking three steps back when concluding our silent prayer of Shmoneh Esrei.

After enjoying the miraculous delivery from the Assyrian forces of Sanncherib, the righteous King Chizkiyahu became mortally ill. He prayed to G-d for a recovery and was given a Heavenly sign by the Prophet Yishayahu that his prayers were accepted (Melachim II 20:1-11). That sign consisted of ten hours of daylight being added to the day. The significance of those ten hours emerges from another passage (Yeshayahu 38:8) in which the prophet explained to the king that these were the hours withdrawn from the day his wicked father, Achaz, died and were now restored. The sun suddenly set ten hours before its time on that day in order that there would not be a lavish burial and eulogies.

This unexpected lengthening of the day for Chizkiyahu created a panic in the royal household of Babylon. The king, Merodach Baladon ben Baladon, was in the custom of dining three hours into the day and then sleeping until the ninth hour. When he arose that day the sun had retreated ten hours distance in the heavens and it was morning. Assuming that his servants had negligently allowed him to oversleep until the next morning he became so incensed that he wished to kill them. They then explained to him that it was still the same day which had been miraculously extended for the recovery of King Chizkiyahu. So impressed was he by this miracle that he sent a gift and letter of greeting to Chizkiyahu (Yeshayahu 39:1). The letter was thus addressed: "Peace greetings to King Chizkiyahu, peace greetings to the City of Yerushalayim, peace greetings to the great G-d."

Nebuchadnetzer, who would eventually become king and destroy the Beit Hamikdash, was the chief royal scribe at that time, but was away when this letter was written. Upon his return he asked his underlings how they had addressed the letter. "Is this how you address such a letter?" he challenged them. "You give G-d recognition as the Supreme Force and you list him last!" In response to his insistence that the order be switched they suggested that, as the critic of their effort, he personally pursue the messenger carrying the letter and change it. After taking four steps in that direction he was halted by the Angel Gavriel. Had he not been halted, noted Rabbi Yochanan, the power he would have gained from displaying such honor to Heaven might have enabled him to destroy.

Maharsha and other commentaries point out that in midrashic sources it is recorded that he took only three steps, steps that gave him the power to destroy the Beit Hamikdash. This is why we conclude our central prayers by taking three steps back in honor of G-d and praying for the restoration of the Beit Hamikdash.

Sanhedrin 96a

"Sing each day, sing each day!" was the counsel given by the great sage Rabbi Akiva. Rashis explanation of this double phrasing is that he meant to urge one who studies Torah to steadily review what he has learned, even if it is as familiar to him as a song. His reward will be the joy and song he will enjoy in the World to Come.

The subsequent support for Rabbi Akivas point brought by Rabbi Yitzchak bar Avudimi causes one of the commentaries to offer an alternative explanation. This sage cites a passage from Mishlei (16:26): "The soul that strives will benefit from that striving because he has focused his mouth [on Torah study]." His explanation is that while a person studies Torah in one place, the Torah strives for him elsewhere (the Torah comes before its Master and begs Him to reveal to the learner the secrets of the Torah and its scope and why? because he has forced himself and focused his mouth on studying Torah Rashi.)

In line with this beautiful idea, Maharsha thus explains Rabbi Akivas advice about singing: If you will sing each day in your study of Torah, the Torah will sing to you each day as its secrets are revealed to you.

A second interpretation is offered by the same author based on an earlier comparison in our gemara made by Rabbi Yehoshua ben Korcho between one who studies but fails to review, and one who plants and does not reap. The Hebrew word for singing "zameir" also means to reap the fruit of a grape vine. If you not only learn Torah but reap its fruits as well through review, then the Torah will also reap profits for you elsewhere.

Sanhedrin 99b