This thoughtless act produces an especially ruinous effect on the weak and those not established in faith. Such people could see Christians eating idol-offerings as a direct betrayal of Christianity. Following others, they could truly betray Christianity themselves. These unhappy ones perished by following people who ate idol-offerings without the least thought of betraying the Christian faith. Yet these became the chief cause of the destruction of the weak.
Warning such people against eating things offered to idols, the Apostle says: "Take heed, lest somehow this liberty of yours become a stumbling block to the weak"; "wounding their conscience"; "you sin against Christ."
According to the explanation of St. John Chrysostom, "The Apostle says, 'Take heed,' arousing in the Corinthians fear, shame, and resolve not to do this. He did not say, 'this knowledge of yours,' or 'your perfection,' which would have sounded more like praise, but 'liberty.' By this he expressed rather their shamelessness, boldness, and pride. He did not say, 'to the brethren,' but 'to the weak,' who are of the brethren. He increases their guilt because they do not spare even the weak, and indeed their brethren."
"Your Master did not refuse to die for him, yet you pay him no attention. You are unwilling, for his sake, to abstain even from an unclean table. You allow him to perish after his salvation has been accomplished, and what is most grievous, for the sake of food."
They sin in this against Christ: first, because He takes to Himself what concerns His servants; second, because those who are wounded are His Body and His members; third, because those who wound the conscience of the weak, through their pride, destroy the work He accomplished by His death.