King James Version
Howbeit there is not in every man that knowledge: for some with conscience of the idol unto this hour eat it as a thing offered unto an idol; and their conscience being weak is defiled.New International Version
But not everyone knows this. Some people are still so accustomed to idols that when they eat such food they think of it as having been sacrificed to an idol, and since their conscience is weak, it is defiled.Catholic Public Domain Version
But knowledge is not in everyone. For some persons, even now, with consent to an idol, eat what has been sacrificed to an idol. And their conscience, being infirm, becomes polluted