The Sefer Hachinuch writes; “One who is careful with the mitzvah of Birchas Hamazon will always have Parnasah in abundance and in a respectful manner.” One who want to be careful should always bentch while reading the words in a siddur (or bentcher) and not bentch by heart.  ~ Shulchan Aruch w/Mishnah Brurah 185:1, see also Be’er Haitaiv

The Sefer Hachasidim writes; “A person once died and appeared to a relative in a dream and told him that he is being judged every day for not having been careful to say all his berachos with proper kavannah.” Shulchan Aruch w/Mishnah Brurah 185:1, see also Be’er Haitaiv

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