Actually the holy names do not require a material instrument such as our tongue or finger to manifest Themselves. If Nitainam Prabhu so desires, He can manifest Himself without our assistance at any moment He wills. He is swaraat, completely independent, just like Nitai. These syllables of Nitainam are fully transcendental and divine. They are not ordinary. They are from Sri Goloka Dham. The Namakshars are not dependent on any material object to facilitate Their divine appearance. Janma karma ca me divyam. Just as Nitai's appearance is beyond the material phenomenon, it is purely transcendental...so it is in the case of His divine name.
Why is it then that Nitainam Prabhu chooses to appear by the touch of our finger? To show unlimited favour on us!!! Just as Nitai can appear where ever He wills, Nitainam can also manifest where ever He desires. How merciful is Nitainam Prabhu, that although He can manifest anywhere according to His own will, He is using us as His instruments. By doing so, we are also becoming spiritual, due to contact with Him!
Srila Bhaktisiddhanta Sarasvati Thakur Prabhupad has explained that Harinam Prabhu can also descend in His raw form of pure sound vibration from Goloka if He desires, but He chooses to dance on the devotee's tongue.
Nam Prabhu is never bound by any external restrictions. It is to bestow mercy on us that Nitainam Prabhu has agreed to manifest through our touch! That is our maha-bhagya, greatest good fortune. Nitai is showing His unprecedented, causeless mercy on us destitute souls. It is by Nitainam Prabhu's mercy that Harinam also descends from Goloka to our tongue. We should always regard these Namakshars with great reverence and remember that They are here only to shower us with mercy.
Nitaisevak ganer seva abhilashi,