Likewise, if a person falls from his level [of attachment] in the middle of the prayers, he should say the words with even a little bit of concentration – as much as possible. Afterward, he should try to regain his [previous] level, even if it requires many attempts. At first, one should cling to the form of the word,⁸ and then, give the word its soul.⁹, part 2, p. 4d. One should start by applying all of his physical energy,¹⁰ and then the power of his soul will shine in him, as the Zohar states: “When wood does not burn, hit it and it will light.”¹¹ Finally, he will be able to serve G-d with his thoughts alone, without any physical motions. Ibid. p.7a

footnotes: ⁸ Literally, the “body” of the word. ⁹ A person’s ability to concentrate comes from a revelation of the soul. The Baal Shem Tov taught, “Concentration (or “intention”) is the soul, and this is mystical attachment.” When a person puts all of his concentration into the words of prayers, he divests his soul of its physicality. The soul can then enter into the letters, which now give birth to new revelations of G-dliness. See Kesser Shem Tov ¹⁰ Meaning, a person should put all of his physical energy into the prayers, such as by praying in a loud voice, with swaying movements of the body, or with ecstatic gestures. ¹¹ Zohar 3:168a. Pre-chasidic ethical texts interpreted this statement as referring to self-affliction; i.e., breaking the body in order to release the soul. However, the path of asceticism was rejected by the Baal Shem Tov, who stressed the efficacy of loudly-recited prayers and ecstatic physical movements to arouse the concentration and emotions.