Rev Iain Cunningham, Convenor of the World Mission Council, said the minister must consider the abuse faced by believers in Pakistan when he is trying to set up trade deals in the wake of Brexit.
He was speaking to Premier after the Moderator of the General Assembly of the Church of Scotland, Rt Rev Dr Russell Barr, wrote to Mr Johnson (below) about persecution.
"I am alarmed to hear reports of forced conversions of Christians in Pakistan," he wrote.
He said there was a growing threat to the safety and security of non-Muslims in Pakistan and this was making the lives off minorities increasingly difficult.
The moderator urged Mr Johnson to raise the issue with the Pakistani government "as a matter of urgency". It's understood the Foreign Office will write back soon.
Asked by Premier if this meant the topic should be raised during trade negotiations, Rev Iain Cunningham replied: "I think that's a question you'd have to ask Mr Johnson rather than us.
"Who knows? I hope that he would see that this is actually a serious issue and it is a human rights concern that he should be concerened about.
"We shoudn't just be entering into trade agreements without taking those kind of things into consideration."
He stressed, though, that suggestions from some that UK aid should be stopped until Pakistan takes more action on persection "would only hurt" and would not "produce the required effect".
"We leave it to the government to find the best way to make that pressure. We just simply want to bring the situation to the attention of the government and they will know what is likely to make Pakistan do something".
Christians make up 2 per cent of the population in the country and although no official statistics are available, campaigners think thousands of girls under 18 are forced to convert to Islam every year.
A Foreign Office Spokeswoman said: "It is vital that Pakistan guarantees the rights of all its citizens, regardless of their gender, faith or ethnicity.
"We regularly raise the issue of freedom of religion and belief at senior levels within the Pakistan government."
Rev Iain Cunningham speaking to Premier's Antony Bushfield: