Before treating the matter of a military crown I think we must first ask whether military service is appropriate for Christians at all. What is the point in talking about incidental matters when the assumptions which they rest on are wrong from the start? Do we think that one can rightfully superimpose a human oath on one made to God? And that a man can answer to a second lord once he has acknowledged Christ? And that he can abjure father, mother and all his neighbours when the Law prescribes that they be honoured and loved next to God and that the Gospel holds them in the same high esteem, valuing only Christ above them? Is it right to make a profession to the sword when the Lord has proclaimed that the man who use it will perish by it?
Will a son of peace who should not even go to court take part in battle? Will a man who does not avenge wrongs done to himself have any part in chains, prisons, tortures and punishments? Will he perform guard duty for anyone other than Christ, or will he do so on the Lord’s day when he is not doing it for Christ Himself? Will he stand guard at the temples which he has forsworn? Will he go to a banquet at places where the apostle disapproves of it? At night will he protect those (demons) that he has exorcised during the day, leaning and resting on the spear that pierces the side of Christ? Will he carry the standards that rival Christ’s? Will he ask the commander for a password when he has already received one from God?
– Tertullian