1-corinthians 8:9

Heed - To be careful to consider.

But take heed - Lest by frequenting such feasts and eating things offered to idols, under the conviction that an idol is nothing, and that you may eat those things innocently, this liberty of yours should become a means of grievously offending a weak brother who has not your knowledge, or inducing one who respects you for your superior knowledge to partake of these things with the conscience, the persuasion and belief, that an idol is something, and to conclude, that as you partake of such things, so he may also, and with safety. He is not possessed of your superior information on this point, and he eats to the idol what you take as a common meal.

But take heed - This is the reply of Paul to the argument of the Corinthians in 1 Corinthians 8:8. "Though all that you say should be admitted to be true, as it must be; though a man is neither morally better nor worse for partaking of meat or abstaining from it; yet the grand principle to be observed is, so to act as not to injure your brethren. Though you may be no better or worse for eating or not eating, yet if your conduct shall injure others, and lead them into sin, that is a sufficient guide to determine you what to do in the case. You should abstain entirely. It is of far more importance that your brother should not be led into sin, than it is that you should partake of meat which you acknowledge 1 Corinthians 8:8 is in itself of no importance."

Lest by any means - μή πως mē pōs. You should be careful that by no conduct of yours your brother be led into sin. This is a general principle that is to regulate Christian conduct in all matters that are in themselves indifferent.

This liberty of yours - This which you claim as a right; this power which you have, and the exercise of which is in itself lawful. The "liberty" or power ἐξουσία exousia here referred to was that of partaking of the meat that was offered in sacrifice to idols; 1 Corinthians 8:8. A man may have a right abstractly to do a thing, but it may not be prudent or wise to exercise it.

Become a stumbling-block - An occasion of sin; see the note at Matthew 5:29; also see the note at Romans 14:13. See that it be not the occasion of leading others to sin, and to abandon their Christian profession; 1 Corinthians 8:10.

To them that are weak - To those professing Christians who are not fully informed or instructed in regard to the true nature of idolatry, and who still may have a superstitious regard for the gods whom their fathers worshipped.