In an article for a newspaper Douglas Alexander says too often politicians won't speak up for Christians because they're fearful of offending other religions.
The Shadow Foreign Secretary is a committed Christian and said anti-Christian persecution should be treated the same as anti-Semitism or Islamophobia.
Writing in the Daily Record he said: "People of all faiths and none must not stand by in silence for fear of offence. Just like anti-Semitism or Islamophobia, anti-Christian persecution must be named for the evil that it is and challenged by people of faith and of no faith.
"To do so is not to support one faith over another - it is to say that persecution and oppression of fellow humans in the name of any god or ideology is never acceptable and is morally repugnant."
The politician said not enough of his colleagues were speaking out against the persecution of Christianity in Iraq and Syria because they were fearful of offending people of other faiths.
"In an age when secularism is more common, too many politicians - through a misplaced sense of political correctness or embarrassment at "doing God" - seem to shy away from discussing any matters related to faith," he said.
Christians are the victims of 80 per cent of all acts of religious discrimination and face persecution in more than 60 countries.