Quotation for Nedarim 123:13

Before reciting a berachah you must be sure which berachah you are required to recite, so that when you mention Hashem's Name which is the principle part of the berachah, you will know how to conclude the berachah. It is forbidden to do anything else while reciting a berachah. Do not recite the berachah hurriedly but think of the meaning of the words. The Sefer Chassidim states: "When you wash your hands or recite the berachah on fruit or on the performance of a mitzvah,—berachos which everybody knows— you should direct your attention to recite them in the Name of your Creator Whose goodness is bountiful, Who granted you the fruit or bread for your pleasure, or commanded you to perform the mitzvah. You should not recite the berachah automatically, out of habit, spouting words from your mouth without thinking of their meaning. On account of such practice Hashem's anger was kindled, and He sent us word through the prophet, Isaiah, saying: "Because this people approaches [Me] [only] with their mouths and honor Me [only] with their lips and their heart is distant from Me and their reverence for Me is merely perfunctory."¹Isaiah 29:13. The Holy One Blessed is He said to Isaiah, See how the deeds of My children are merely external and they adhere to them [only] as a person adheres to and practices a custom of his forbearers; they enter My house and pray to Me the designated prayers merely as a custom of their fathers but not with their whole hearts. They wash their hands, and recite the berachah over the washing and then break bread and recite the hamotzi, they drink and recite the berachah out of habit. When they recite the berachos they have no real intention of praising Me. Therefore, His anger was fierce and He swore by His great Name to destroy the wisdom of their Sages who know Him and still praise Him perfunctorily, without sincerity as it is written thereafter: "Therefore I shall do yet more … and the wisdom of their Sages will be lost."²Isaiah 29:14. Therefore our Sages warned us regarding this and said: "Fulfill [your] obligations for the sake of the Creator etc."³Nedarim 62A. This concludes his [Sefer Chassidim's] remarks. It is proper to accustom yourself to recite the berachos aloud because the voice arouses concentration.