May one be mi’Chalel Shabbos for the purpose of having a Tzadik daven for a mortally ill person?
A number of years ago is a town called Zlutchov in Galicia the Dayan of the city permitted a Chasid of Belz to have a non-Jew write down the name of a mortally ill person and bring it to the Sar Shalom of Belz to who was in a neighboring town so that the Tzadik will Daven for him. When the Sar Shalom received the name he was disturbed by the Chilul Shabbos and he commented, I will now have to put in extra effort in my Tefila so that the Chilul Shabbos will not be for naught.
R. Shlomo Kluger upon hearing of the story took great umbrage to the Chilul Shabbos (even though it was only an Isur mid’Rabbanan) and he wrote a letter to the town elders decrying the Heter that was given and he said that it is forbidden to be Mechalel Shabbos for the purpose of having someone Daven for the Choleh. It is only permitted to be Mechalel Shabbos for something that will be a Refuah for the Choleh. Tefila is not a Refuah it is a request for Hashem Yisborach to cure the Choleh. Hashem Yisborach could cure the Choleh without our Tefilos. Hashem knows what is in our hearts and He knows that if it weren’t Shabbos we would ask the Tzadik to Daven for us.