Middletown Borough Council in the US state of Pennsylvania approved Mark Hovan's penalty, following a recommendation by local police chief George Mouchette.
Mr Hovan told the local Press & Journal news website: "I never lied about it".
The patrol officer was summoned to a meeting with Mr Mouchette on 7th November in a letter which made four accusations of 'neglect of duty' and 'inefficiency' against him.
Mr Hovan told the Press & Journal said he had been going to church during shifts throughout his 19-year service at Middletown Police Department in order to mark six Catholic holy days.
A devout Catholic, Mr Hovan previously received a warning after he attended Mass on 8th January 2017.
It is unclear whether the patrol officer will be paid during his suspension period, a punishment which was borough councillors passed by four votes to one - plus one abstention.
In an earlier interview with the Press & Journal, Mr Movan claimed his constitutional right to practise freedom of religion had been "infringed upon" and that the police department had made "no accommodation" for his religious beliefs.