This story happened in the summer of 1979. Yossi K. had decided that the time had come to replace his tefillin with a nicer pair. He had recently begun to study Chabad Chassidism and decided that his new pair had to conform to all Chabad customs. He entered the Judaica store and told the salesman, “I am looking for the nicest tefillin you have, according to Chabad custom.”

The seller nodded and pointed out all the superior qualities of the product. “The scrolls were written by a G-d-fearing sofer [scribe]. The battim [cases] were likewise made with all stringencies.” Yossi was convinced. The next day, he happily put on the new tefillin that he had purchased.

Several weeks later, Yossi was caught up in a number of personal problems, and decided to write to the Lubavitcher Rebbe to request his advice and blessings. He did not want to make any major decisions without asking the Rebbe first.

Yossi was impatient, and after waiting a sufficient amount of time for the letter to come, he called the Rebbe’s secretariat and asked if the Rebbe had answered him. The secretary informed him that the Rebbe had replied to his letter and the letter had already been mailed. Yossi asked if he knew what the letter said. The secretary unfortunately did not remember. “I’m sorry, you will have to wait two or three weeks until the mail reaches from New York to Israel.”

In the coming weeks, Yossi checked the mailbox anxiously each day, hoping that the letter from the Rebbe arrived. As the months went by, he decided to call the Rebbe’s secretariat once more. The line was constantly busy, and Yossi realized that they were dealing with a high volume of calls and letters to prepare for the new year. Finally someone answered, but his impatience was evident. “The letter was already sent,” said the secretary. “I do not know why it has not yet arrived. Yossi knew that the secretariat kept a copy of every letter the Rebbe sent, and he asked them to find a copy of his letter and mail it to him.

During the month of Elul, it is the custom of chassidim to have the tefillin and mezuzot inspected to make sure they are kosher. Yossi was familiar with this custom and although the tefillin were new, he sent them to be inspected by an expert, experienced sofer.

“Perfectly kosher,” smiled the sofer to Yossi when he returned the tefillin.

Meanwhile, he had not yet received the copy of the Rebbe’s letter as requested. Some friends of Yossi were flying to New York for the Tishrei holidays, and Yossi asked them to find out what happened to his letter. However, due to the hectic time his request was forgotten.

Yossi was disappointed. The Rebbe had written him a letter, but no one knew what was written in it or had any explanation why the letter was delayed. As a last resort, he wrote a personal letter to the Rebbe’s chief secretary, Rabbi Chaim Mordechai Isaac Hodakov, describing his dilemma. He ended with a request to please find the missing letter. He did not send his letter in the mail. Instead, he gave it to a friend who was flying to New York for the month of Kislev, asking him to personally deliver it.

Within two weeks, Yossi received the awaited answer from the Rebbe. He opened it with awe. One of the Rebbe’s instructions was to check the tefillin, and Yossi was not sure what to do. There were three good reasons to believe the tefillin did not need to be checked. For one, they were new, and they had recently been checked. In fact, they were checked after the Rebbe wrote his instruction to check them, even though Yossi had not yet received the letter.

But friends advised him not to forego checking the tefillin. “If the Rebbe’s answer reached you now, it shows that it pertains to now, not to the time when it was written.”

Yossi took their advice and gave his tefillin to be checked by a different sofer. “I received an instruction from the Rebbe to check them,” Yossi informed the sofer.

A few hours later the sofer called Yossi. The news was not good. The sofer had found a serious error—in one of the sections, a complete word was missing!