Loss of speech occurs by the physical disorders in the organs of speech. Powerful loss of it may occur by psychological disorders. Physical disorders respond to physical treatment. While the psychological malfunctioning hardens in response to physical treatment, it readily responds to a psychological approach. The Spirit, when evoked, acts through any opening the embodied being gives.
A boy of 19 lost his speech and his family had not discovered the fact for a few days, as the boy never spoke much. He was hospitalised in the hope of some recovery. The boy's family gradually understood that there was no treatment for this. The only consolation they all got was they could pray to God. Almost everyone prayed. There was no change in the boy's condition nor was there inner calm that comes from prayer.
The boy's brother met an acquaintance during bus travel from whom he heard of calling the Spirit. As the boy could hear, the brother communicated the information to him. He too tried on his part. Being new to this kind of effort, no one could do the right thing. On the first day of feeble efforts by so many, the boy spoke one word after about ten days of affliction.
This was great encouragement and everyone redoubled their efforts, i.e. fumbled around after a fashion. Invoking the Spirit is a spiritual process to which tradition has various methods. The best thing is to understand the existence and power of the Spirit and by the mental will summon it to action. This is to activate the mind. Mind, conceding its inability and falling silent, stirs the Spirit into action which peeps into our surface for a trice. This is enough to solve the problem. For yoga the Spirit needs to remain on the surface forever. The energetic efforts of everyone gave the boy his full speech the next day showing itself in a graded fashion.
Faith is described as the knowledge of the soul. Mind that does not have that knowledge knows that ultimately a work will come around, as it knows that that knowledge is in the soul. Mind itself getting the knowledge of the soul makes the mind formidable when it courts adventures. In yoga, our vital energies are known as 'vital'. One becomes lucky, meets with unfailing success, etc. when his vital has the spiritual knowledge.