CC Ādi 17.32
nāma-sūtre gāṅthi’ para kaṇṭhe ei śloka
Raising my hands, I declare, “Everyone please hear me! String this verse on the thread of the holy name and wear it on your neck for continuous remembrance.”
When chanting the Hare Kṛṣṇa mahā-mantra, in the beginning one may commit many offenses, which are called nāmābhāsa and nāma-aparādha. In this stage there is no possibility of achieving perfect love of Kṛṣṇa by chanting the Hare Kṛṣṇa mahā-mantra. Therefore one must chant the Hare Kṛṣṇa mahā-mantra according to the principles of the above verse, tṛṇād api su-nīcena taror iva sahiṣṇunā. One should note in this connection that chanting involves the activities of the upper and lower lips as well as the tongue. All three must be engaged in chanting the Hare Kṛṣṇa mahā-mantra. The words “Hare Kṛṣṇa” should be very distinctly pronounced and heard. Sometimes one mechanically produces a hissing sound instead of chanting with the proper pronunciation with the help of the lips and tongue. Chanting is very simple, but one must practice it seriously. Therefore the author of Śrī Caitanya-caritāmṛta, Kṛṣṇadāsa Kavirāja Gosvāmī, advises everyone to keep this verse always strung about his neck.