Wakass Haruf taught at Birmingham's Golden Hillock Academy - one of the schools caught up in the so-called Trojan Horse affair.
A professional panel heard he told pupils other faiths were "ignorant".
He was found guilty of professional misconduct but other allegations against him were not proven.
The National College for Teaching and Leadership (NCTL) panel was told the comments were made at a prayer meeting at the school in July 2013.
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The panel found that allegations Mr Haruf told pupils "we have the true religion, not like those ignorant Christians and ignorant Jews" were proven.
He was found to have brought his profession into "disrepute" by the comments, but the panel concluded it was possible this was "an unintended consequence arising from his choice of language" on one occasion.
He was also accused of discussing the promotion of Islam in the school over an exchange of messages with other teachers in a Whatsapp social media group.
However, the panel did not find Mr Haruf was actively involved in influencing the religious education of pupils at Golden Hillock Academy, or Park View Academy in Alum Rock, where he previously taught.
Therefore, it ruled Mr Haruf should not be banned from teaching.
A Department for Education spokesperson said: "Intolerance has no place in the classroom and all schools are required to actively promote the fundamental British values of mutual respect and tolerance of those of different faiths and beliefs.
"We expect all schools to carry out the appropriate checks when employing teachers and consider all the relevant information."
The Trojan Horse affair was sparked by an anonymous letter which claimed hard-line Muslims were trying to get their own members on to governing bodies to try and oust head teachers at some schools in Birmingham.
As a result five Birmingham schools, including Golden Hillock, were put into special measures by education watchdog Ofsted.
The school has since joined the Ark network of academies.
A maths teacher found guilty of misconduct after telling pupils "Islam is the true religion" can continue to teach, a professional panel has ruled.