Nabil Maaloul made the strong retort in an interview with Tunisian state-run television.
"I have one thing to say in regards to the criticism… anyone who has attacked me for reading the Fatiha needs to seek medical treatment for themselves," Maaloul said, referring to the first Surah (chapter) of Islam’s Holy Book.
"We have grown up with the Quran and the Fatiha. When we had exams in school our mothers would read the chapter for us. The Fatiha is said in all of our prayers from dawn until dusk," the coach added.
A video of Maaloul and his team reading the Fatiha in the changing rooms ahead of their first World Cup game against England gained traction on social media last week.
Mukhtar al-Halfawi - a local media pundit - lashed out at the team after they lost the match and said their reading the religious verses was an act of "witchcraft and superstition".