The tenacious bonds tying Rabbi Menachem Mendel to his great rebbe, the Vilna Gaon, were built of love and respect intertwined.
As R' Mendel himself wrote in the introduction to one of his Kabboloh seforim, "I served my Rebbe with all my strength. In those two-years-less-a-third, I did not move away from him day or night. Wherever he went, I went, and wherever he lodged, I lodged too." He continues that it was only the Gra's merit that enabled him to go up to Eretz Yisroel, where he lived first in Tzfas and then in Yerushalayim.
In his introduction to the Biur HaGra on Mishlei, R' Mendel writes "...And if man were to live a thousand years he would not be able to reach the edge of the greatness of the Gra."
R' Menachem Mendel was chosen by the Vilna Gaon to commit the latter's chiddushim to writing. R' Mendel later related the sequence of events. Rabbeinu the Gra was already advanced in years and was close to completing his commentary on Shir Hashirim.
Together with his son and talmid, he entered a secluded room and instructed them to close the windows and shutters. After lighting many candles in honor of the Torah, the Gra dictated the last few chiddushim as R' Mendel sat and wrote them down. Then, raising his eyes heavenward, he thanked HaKodosh Boruch Hu for enabling him to reach the light of the whole Torah in its entirety.
The Gaon warned the other two present that they should not disclose this slip of the tongue of his to anyone. It was only after the Gra passed away that R' Mendel of Shklov related those amazing facts to his friend, R' Yisroel of Shklov, who printed them in the introduction to his sefer - Pe'as HaShulchon.
The sefer Mishlei with the commentary of the Gra, acclaimed and accepted by Jewry worldwide, was written solely by his talmid R' Mendel of Shklov. However, R' Mendel admits that not all the peirushim are exactly as the Gra told him. "There are some things that I understood from the Gaon's hints and (after writing them) I asked if I had expressed his opinion, and he nodded his head to me."
Likewise, R' Mendel sat together with the Gra on the Seder night and later wrote down all the divrei Torah he had heard, eventually printing the Haggadah Shel Pesach with the commentaries of the Gra.
Upon fulfilling his dream of going up to Eretz Yisroel, R' Mendel opted for the city of Tzfas, city of the kabbalists. After a while, he moved to Yerushalayim, where the famous Churvah Shul had just been acquired back from the Arabs. There R' Mendel founded a beis knesses, where the minhagim of the Vilna Gaon were followed.
Times were difficult for the Jews of Eretz Yisroel. They suffered much harassment and worse at the hands of the Arab rulers.
In the diary of a gentile who came to tour the Holy Land, a detailed account is written of his impression of Rabbi Menachem Mendel and the pitiful situation of the Yidden living in Yerushalayim.
At first he praises in admiration the love and fear of Hashem of R' Mendel, noting that there is none like him in Torah greatness the world over.
" . . . I would like my readers to know and perhaps have an insight of the troubles that befall the Jews of Jerusalem.
"One night, as Rabbi Mendel was preparing to go to sleep, he was startled by a harsh knocking accompanied by coarse roars, at his door. Hurrying to discover the cause he went towards the door, but before he could reach it, the wood splintered and men of the Arab military burst into the small room, sabers drawn in their hands.
"Grabbing R' Mendel by his beard, they dragged him outside and, together with several members of his family, he was thrown into a prison cell.
"There the terrified captives were told that if ten gold `Kissim' were not paid for their ransom, they would be tortured.
"Their cruel captors described sadistic methods they were wont to use, such as holding hot iron rods to their heads or screwing sharp nails to the palms.
"Gathered outside the prison the anguished Jews of Jerusalem were warned of the dire consequences if they do not bring the required sum.
"They, with their meager means, immediately began collecting together all they could lay their hands on. After much haggling, they managed to persuade the Arabs to lower the fine to four and a half Kissim of gold, but even this was difficult to raise.
"Finally, after selling almost all their personal belongings, the money was paid and the prisoners released.
"Perhaps now you'll have an idea," continues the gentile writer, "of the suffering endured by those European Jews who leave house and home to live in the holy city of Jerusalem. They immediately became prey to the wild beasts around them."
It is to be noted that R' Mendel did not become dispirited or dejected from the travails he suffered as a result of his coming to Eretz Yisroel. On the contrary, he encouraged other talmidei chachomim, disciples of the Vilna Gaon, who yearned to learn Torah in the Holy Land, to indeed leave Europe and take the difficult step which was worthwhile despite the hardship involved.
An amazing revelation of the Gra's wisdom and greatness is retold by R' Mendel, who merited to hear them from the Gaon himself.
The Gaon once told R' Mendel that if the heretical philosopher Aristotle were to come to him, he would bring down the sun, moon, and planets onto his table and prove to him that it is Hashem who rules and dictates the planets and not the forces of nature that run their own course. He added that Shimon Hatzaddik, who lived at the time of Aristotle, could have done the same, but was never given the opportunity, for the apikorus had no intentions of listening to him.
Listening to the Gaon's words, R' Mendel was shocked and awed into silence. However, the Gaon calmed him down, saying "What's the big wonder? With the mention of one of the holy sheimos, I would be able to carry this out."
The fact that the Gaon revealed this to R' Mendel gives us an idea of the greatness he felt his talmid was destined for.
R' Mendel toiled in the Toras HaKabboloh, which he considered a necessity to learning Torah. He wrote in his commentary to the Gra's explanation of Mishlei, that as long as a person doesn't know the peirush according to its sod — it's kabbalistic meaning — he will not fully understand the pshat in its literal sense either. Only once he has learnt the sod can he then learn the pshat. He adds that his Rebbe, the Gaon, confirms that he did not explain a single posuk in Tanach until he had learnt its meaning al pi Kabboloh.
Similarly, the great Rabbi Yisroel of Shklov, zt"l, cites in the hakdomoh to his sefer Taklin Chadtin — that he heard from R' Mendel that every chiddush of the Gra on mishnayos Sefer Taharos was only thought out once the subject was known to him al pi Kabboloh.
His great sefer Mayim Adirim on Idra Zuta acquired its own reputation immediately as all mekubalim took it up.
It is told that for a few years the sefer was in constant use on the table of the Divrei Chaim of Zanz. According to the mekubal Rabbi Shmuel Landau of Sandova, one of the greatest of the Belzer Chassidim, the Zanzer had no idea who the author of the sefer was, but cherished it and used it continually.
Due to the overwhelming demand for this great work, Mayim Adirim was printed twice in one year, both in Vilna and Galicia.
In his introduction to Pe'as HaShulchon, Rabbi Yisroel of Shklov notes that Rabbi Menachem Mendel left ten (!) seforim of Kabboloh.
Of late, volumes of handwritten manuscripts of Reb Mendel were discovered and printed by HaRav Shmuel Arye Stern of Yerushalayim called, "Kisvei HaRamam MiShklov."