Rabbi Yehudah Aryeh Leib (known by the title Sefas Emes) is strongly connected to the Parsha of VaYechi. He was nifter on this Shabbos in the year 5665. His last Maamar (Torah talk) was said in connection to this Parsha.
בראשית מט,א: וַיִּקְרָא יַעֲקֹב אֶל־בָנָיו וַיֹאמֶר הֵאָסְפוּ וְאַגִּידָה לָכֶם אֵת אֲשֶ ר־יִּקְרָא אֶתְכֶם בְאַחֲרִּ ית הַיָמִּים:
The Medrash tells us that we have the merit of Krias Shema from the following incident:
All the children of Yaacov were gathered at his bedside to hear his last words. Yaacov wished to share information about the “end of days” but was unable to do so. Perhaps there was a weakness in the heart of one of his children (was not totally devoted to LeShem haShamayim)?
The children answered, שמע ישראל אבינו “Listen our father Yisrael” ה' א-לקינו ה' אחד “There is no weakness in our hearts we are all dedicated to HaShem.”
Why is this short tefilah treasured and elevated above all else?
The Sefas Emes emphasizes that this gathering of all the Jews of that generation was a preparation for all future generations. (The acts of our forefathers are a siman for us, their children; and this was the one of the last acts of Yaacov) When the children of Yaacov accepted the Torah provided the ability for future generations to accept the Torah. Every future gathering of the Jews which was LeShem ah Shamayim is “moresha Kehilas Yaacov.” Therefore each Shabbos is a proper time for a gathering of the Jews.
Therefore it says in Kabalah “not to fear My honor” that it is known that all gathering that are LeShem haShamayim bring honor to HaShem and called EMES as it says ה' הוא א-לקים אמת והוא מתקיים .
Further Krias Shema which is said in a holy gathering of the Jews is testimony that HaShem is only with the nation of Yisrael. With this HaShem is Elokim and it will be everlasting like it is written:
משלי יב,יט : שְ פַת־אֱמֶת תִּכּוֹן לָעַד
“Words of truth are established forever”
This was the holy Rebbe’s last public words. Therefore, after his petirah when publishing his talks on the Torah, his children decided to title the Sefer שְ פַת־אֱמֶת in honor of his last part of his last Maamar and as an indication of his holy life.
The Sefer became an international success, so much that Rabbi Yehudah Aryeh became known by the title of the Sefer, Sefas Emes.
The Sefas Emes, Rebbe Yehudah Leib Alter (1847-1905) was the 2nd Rebbe of the Gerer Chassidim and the grandson of the Chiddushei HaRim. He was orphaned at the age of one and raised by his grandfather.
He was a child prodigy and studied without interruption for eighteen hours at a time. When he was nineteen, his grandfather, the Chiddushei HaRim passed away and pressure was exerted on Reb Yehudah Leib to assume the mantle of leadership of the Gerer Chassidim. He felt unworthy however, and instead went to Alexander to study under Rebbe Chanoch Henoch.
After only four years, Rebbe Chanoch Henoch passed away, and then Reb Yehudah Leib was left with no choice but to comply with the wishes of the Chassidim to become the leader of the Ger. Under his guidance and leadership Ger became the largest Chassidic group in Poland. The Sfas Emes, named after his magnum opus, was a proponent of expanding the Chassidic community in Israel, and greatly supported activities to that end. His son, the Emrei Emes, escaped the Nazis, came to Israel and rebuilt Ger, restoring it to its former glory.