Romans 14:13-14 — Let us not therefore judge one another any more: but judge this rather, that no man put a stumblingblock or an occasion to fall in his brother's way.
I know, and am persuaded by the Lord Jesus, that there is nothing unclean of itself: but to him that esteemeth any thing to be unclean, to him it is unclean.
judge this = let this be your decision
persuaded by the Lord — not from his own reasoning
of itself = of its own nature
Our conscience isn't always the best guide to right and wrong, but it's always wrong to go against it.
unclean — ceremonial — not referring to moral impurity