Musar zu Jeschijahu 29:13

Never eat or drink anything without making the appropriate blessings before and after with as much zeal as you can. Comprehend the meaning of the blessing. Cover your head when mentioning God’s Name, and close your eyes. When making a blessing or praying to God be not as it says, “With their mouths and lips they honored Me, but their hearts were distant from Me” (Isaiah 29:13).

And we find with the people of Sodom that they were very bad to God on several [plains] of corruption, such as theft, extortion, perversion of justice and forbidden sexual relations. Nevertheless, Scripture mentions that their souls were lost and destroyed by the sin of nullifying charity, as it is stated (Ezekiel 16:49), “Only this was the sin of your sister Sodom; arrogance - plenty of bread, etc.; yet she did not support the poor and the needy.” And it is stated about the people that do not arrange their thoughts to constantly reflect on the fear of God (Isaiah 29:13-14), “And its worship of Me has been a commandment of men, learned by rote. Truly, I shall further baffle that people with bafflement upon bafflement.” And it is stated (Jeremiah 12:1-2), “Why does the way of the wicked prosper, etc. [...] You are present in their mouths, but far from their thoughts.” And it is stated (Psalms 23:27), “Those who keep far from You perish.”

And let one not wonder that we actually see people who after the saying of "Remember," and, sometimes, even at the time of its saying, speak lashon hara. Where, then, is the assurance of the Torah? But, in truth, is it not written of words of Torah (Devarim 32:47): "For it is not an empty thing from you" — If it is empty, it is from you [i.e., because of you] that it is empty. And there has been fulfilled in us, in our many sins, the words of Isaiah the prophet, may peace be upon him (Isaiah 29:13): "Because this people has drawn near. With its mouth and its lips it has honored Me, but its heart is far from Me." For we say "Remember" only with our mouths, but we do not remember at the time of doing. And if a man brought it up to his heart to fulfill the remembrance as the Blessed L-rd has commanded us, it would certainly be of great avail in rescuing us from this sin.