It is customary to say Tehillim to ask Hashem to heal someone who is ill. I want to know how this works.
One possible mechanism is that the Tehillim are the praises of Hashem which must come before a request to Him. In this mechanism, the prayer (Mi Shebeirach … ) which follows the Tehillim is most important.
Another possible mechanism is that the recitation of the Tehillim acts a merit for the sick person and through that merit s/he should be healed. In this case, one might think that a prayer would include words like “in the merit of the Tehillim we have recited”.
So, what is the mechanism and how does it link to prayers for the recovery of the sick person?