Why does Paul say that wounding a weak brother's conscience is a sin against Christ?
Paul says wounding a weak brother's conscience is sin against Christ because Christ died for that weak brother, and the Lord understands his weakness. The mature believer may have freedom, but if his knowledge emboldens the weak to act against conscience, the weak may stumble, and Christ is offended.
Les explains that Paul contrasts the believer who is grounded in the faith with the weak brother who still has compunctions. The strong believer may not worry about such things, but he must consider the poor fellow who is still weak. When the mature believer wounds that weak conscience, he sins against Christ, because the Lord understands where the weak person is and where the mature person is, and He knows they have the wherewithal to make it a level playing field. Paul then says that if meat makes his brother offend, he will eat no flesh while the world stands, lest he make his brother offend. Les notes this is basically what Paul said back in Romans: if something does not hurt you but bothers the weak believer, then for his sake, do not do it.
But when ye sin so against the brethren, and wound their weak conscience, ye sin against Christ.
More Questions
Whose conscience is it that gets wounded, and does a mature believer need to worry about his own?
The conscience Paul speaks of being wounded is specifically the weak conscience, and the mature believer who is grounded in the faith has no more compunctions, but the weak brother must still be taken into consideration — so watch out for that weak brother.