סימן קיט סעיף ו

מִי שֶׁאֵינוֹ יָכוֹל לִלְעֹס מַצָּה, מֻתָּר לִשְׁרוֹתָהּ בְּמַיִם לְרַכְּכָהּ, וּבִלְבַד שֶׁלֹּא תְהֵא נִמְחָה לְגַמְרֵי. וּמִי שֶׁהוּא זָקֵן אוֹ חוֹלֶה וְאֵינוֹ יָכוֹל לְאָכְלָהּ שְׁרוּיָה בְּמַיִם, יָכוֹל לִשְׁרוֹתָהּ בְּיַיִן אוֹ בִּשְׁאָר מַשְׁקִים. כְּשֶׁשּׁוֹרִין אֶת הַמַּצָּה לָצֵאת בָּהּ, צְרִיכִין לִזָּהֵר שֶׁלֹּא לִשְׁרוֹתָהּ מֵעֵת לְעֵת כִּי אָז נֶחְשֶׁבֶת כִּמְבֻשֶׁלֶת וְאֵין יוֹצְאִין בָּהּ. וְגַם צְרִיכִין לִזָּהֵר בִּשְׁאָר דְּבָרִים, שֶׁלֹּא יַפְסִיד דִּין לֶחֶם. עַיֵּן לְעֵיל סִימָן מ"ח סָעִיף ה'.

If someone is unable to chew the matzah, he is permitted to soak it in water²⁰It is also permitted to have the matzah ground up, so long as it equals a kazayis of unbroken matzo. (Biyur Halachah 461:4) to soften it,²¹This leniency applies only when a whole matzah is soaked in one piece, but if it is broken into pieces and then soaked until the water becomes discolored from the matzah, it cannot be used to fulfill the mitzvah, as it is no longer considered bread. These rules applies only to soaking, but if the matzah was boiled, or soaked in boiling water, it is not permissible under any circumstances. (Mishnah Berurah 461:17,18,20) provided it is not completely mashed. An elderly or sick person, who cannot eat matzah, when soaked in water, may soak it in wine, or in any other beverage.²²A healthy, young person cannot fulfill his obligation, if the matzah was soaked in any liquid, except water. (Ibid. 461:18) When you soak the matzah, with which you want to fulfill the mitzvah (of eating matzah), you must be careful not to soak it for twenty-four hours, for it would then be considered as if it were cooked and you could not fulfill the mitzvah with it. You must also be careful, in other respects, that the matzah should not lose its status as bread. See Chapter 48:5 above.

תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)