More than anything else, one must prepare himself mentally before doing any mitzvah and before reciting any blessing, and especially before uttering the exalted Name of Hashem — for if one does this suddenly, without premeditation, then it is like a body without soul. The message of Hashem to the prophet Yeshayahu is well-known: The Lord said: Inasmuch as this people has drawn close, with its mouth and with its lips it has honored Me, yet it has distanced its heart from Me — their fear of Me is like rote learning of human commands — therefore, behold, I will continue to perform more wonders against this people etc. (Yeshayah 29:13-14). Heaven protect us!
Therefore, a God-fearing person, who greatly desires mitzvos, will stop to think before doing any mitzvah or before every prayer and blessing: What is this mitzvah about? What does it mean? How and in what manner should it be done? He will prepare himself and arouse his soul to do it with awe, love, and great joy so that it should be done in a manner that it will be pleasing to God Above, so that he will not toil for naught nor produce for futility. This is a fundamental principle in efforts to perfect body and soul. One who does all this will find peace and will never falter. Therefore, be strong and resolute to do it, and “one who comes to purify himself — Heaven assists him.”