A Malharganj police station officer said the victim, Gajendra Sharma (21), was training to be a priest under the tutelage of head priest of Lal Mandir in Bada Ganpati area since the last one-and-half years.
The victim, who hailed from Narsinhapur district, had hanged himself last night and the suicide came to light this morning when some devotees turned up at the temple, police said.
The suicide note blamed the head priest for the extreme step, they said.
Further investigation is underway.