Amen at the Seudas Tzaddikim in Gan Eden
Sefer Hanavon (printed in Kovetz Al Yad, 16 1, p. 220) cites a Midrash about this subject: “Anyone who answers amen in this world merits to say it at the seudah of the livyasan, as it says (Tehillim 89:53): “Baruch Hashem l’olam amen v’amen.” In the writings of the sages of Yemen, another Midrash is cited on this subject: “Someone who answers amen in this world merits to answer amen in Olam Haba, at the seudah of the tzaddikim in Gan Eden, and when Dovid Hamelech will make a brachah, he will answer amen.” (Eitz Chaim on the Techalel, Shacharis for weekday p. 23)
Source of the Takanah of Yehei Shemei Rabbah
In Siddur Chassidei Ashkenaz (p. 75), it is brought that based on this Midrash it was instituted to say in Kaddish “Yehei Shemei Rabbah mevarach l’olam ul’olmei olmaya,” meaning that even in Olam Haba, Hashem’s Name will be praised by those who praised Him by answering amen in this world.
Therefore 'The One Who Answers Amen Is Greater'
Based on this, Harav Yechiel Heilperin, author of Seder Hadoros, explained why Chazal instituted (Brachos 53b) that “the one who answers amen is greater than the mevarech.” When one answers amen in this world, he merits for that to answer it also in Olam Haba, but the mevarech does not merit this wondrous virtue. (Sefer Halikutim [Rav Y. Heilperin] Vol. II, Teshuvah 24)
‘Vesham Todah Nezabe’ach’ – In the Merit of Answering Amen
The Mashgiach Harav Mattisyahu Salomon explained that the beginning of the piyut of Ma’oz Tzur is built on these words of Chazal. “Ma’oz tzur yeshuasi Lecha na’eh leshabe’ach” – when one praises and thanks his Creator with completeness and emunah for every good thing and blessing that he receives in this world, then when “tikon Bais Tefillasi” – the Bais Hamikdash will be built, “vesham todah nezabe’ach” - he will merit to continue to serve Hashem and praise Him completely by bringing the Korban Todah and answering amen. (Kovetz Nehorai, 5768 p. 69)
Birchos hashachar k'halachah: Aloud, with kavanah, bechavrusa
