1 Corinthians 10:15 - Ellicott's Commentary On The Whole Bible

I speak as to wise men. — These words are not hypothetical; they imply the point of view from which the Apostle is now regarding his readers — viz., competent to recognise the force of his argument. Having warned them against any participation in idolatry, even such as would be involved in joining in the sacrificial feasts, as dangerous to themselves, he now proceeds to show that such a participation would be derogatory to, and incompatible with, their union with Christ. The identity and intimacy of that union is first established by a reference to the Holy Communion, in partaking of which both the unity of the Church and its union with Christ are vividly expressed.