You should accustom yourself to praying in a low voice, even the verses of praise.⁸⁹ – the section of the morning prayers composed of Psalms. You should cry out in a whisper. Yet, whether you are praying or studying Torah, you should say the words with all of your strength, as it is said, “All my bones will say G-d, who is like You!” (Psalms 35:10). This cry, born out of attachment to G-d, should be in a whisper. Ibid. p. 4b

footnotes: ⁸⁹ The pesukei d’zimrah