John Piper has issued a robust rebuke to Jerry Falwell, president of Liberty University, who urged students to carry concealed weapons on campus after the San Bernadino shootings.

Falwell caused outrage with his address to students, in which he implied that he had a gun in his own pocket and said of Muslim extremists, "let's teach them a lesson if they ever show up here".

In a long post on his Desiring God website, Piper – a highly influential conservative evangelical theologian who is chancellor of Bethlehem College and Seminary in Minneapolis – said that he had contacted Falwell and that their disagreement was "between Christian brothers who are able to express appreciation for each other's ministries person to person".

However, he goes on to make trenchant criticisms of Falwell's view. He says: "The issue is about the whole tenor and focus and demeanor and heart-attitude of the Christian life. Does it accord with the New Testament to encourage the attitude that says, 'I have the power to kill you in my pocket, so don't mess with me'? My answer is, No."

He offers nine considerations backed by copious biblical references. According to Piper, "When Paul says, 'The ruler does not bear the sword in vain' (Romans 13:4), he does not mean that Christians citizens should all carry swords so the enemy doesn't get any bright ideas."

Piper says that Christians should learn to accept unjust treatment without retaliating. He says: "If we teach our students that they should carry guns, and then challenge them, 'Let's teach them a lesson if they ever show up here,' do we really think that when the opportunity to lay down their lives comes, they will do what Jim Elliott and his friends did in Ecuador, and refuse to fire their pistols at their killers, while the spears plunged through their chests?"

He also says: "I think I can say with complete confidence that the identification of Christian security with concealed weapons will cause no one to ask a reason for the hope that is in us. They will know perfectly well where our hope is. It's in our pocket."

He concludes: "Tthe overwhelming focus and thrust of the New Testament is that Christians are sent into the world – religious and non-religious – "as lambs in the midst of wolves" (Luke 10:3). And that exhorting the lambs to carry concealed weapons with which to shoot the wolves does not advance the counter-cultural, self-sacrificing, soul-saving cause of Christ."