Maha Periyavar, who is the omnipotent Parameswara Himself, was camping in Sri Kanchi MaTham, KumbakoNam. The Vyasa Puja was being held there with all glory.
The ChandraMauleesvara Puja being over, all the devotees were in a hurry to get Maha Periyavar's darshan, who was distributing the abhiSeka tIrtham (holy water of ablution) with his holy hands. A devotee's turn came in the line formed by them to receive the prasAdam. Giving him the prasAdam, the Mahaan looked at him, raising his head.
He told the devotee, "You come early tomorrow for the Veda pArAyaNam (recitation)."
What alternative is there to the Mahaan's orders?
As ordered by the Mahaan the devotee came up early the next morning and participated in the occasion of Veda pArAyaNam. When the pArAyaNam was going on, Maha Periyavar made a surprise visit, which was unusual.
He noticed that the bhaktA (devotee) who got his anugraha the previous day was reciting the Vedas with sincere devotion. When reciting the Veda mantras, however, the bhaktA had breathing problems, so he faltered as he recited the shlokas (verses) with difficulty. Kanchi Mahaan realized that the devotee should be having some problem in his throat or lungs.
When it was time to distribute prasAdam after the recitation was over, he called the devotee and asked him to wait.
The devotee seemed to have sanchalanaM (trepidation) in his mind that he did not recite the Vedas properly and the Mahaan had found out some errors in his chanting.
After sometime, a physician came and examined the devotee thoroughly as ordered by the sage. Later when he took the devotee to his hospital and conducted more tests, the physician found out that the devotee had a heart ailment, which caused the falter in the Vedic chanting.
The physician cured the devotee with good treatment that involved no surgery, in accordance with Maha Periyavar's orders.
Some ten days later, the devotee came to have darshan of the Mahaan, who ordered him, "Now you do the Vedic chanting for sometime." The devotee was able to do the chanting without any falter or other problems.
Thus Maha Periyavar saved the devotee from an incoming setback of health.
Know what the devotee said about this? "As mentioned in Thevaram, when we do sincere prayer and worship to Bhagavan, any setbacks and difficulties that should reach us melt away automatically."