1 Corinthians 8:4-7

In this matter, then, of eating food offered to idols, we know that an idol is nothing in the world [it has no real existence], and that there is no God but one. [Deut 6:4] For even if there are so-called gods, whether in heaven or on earth, as indeed there are many gods and many lords, yet for us there is but one God, the Father, who is the source of all things, and we exist for Him; and one Lord, Jesus Christ, by whom are all things [that have been created], and we [believers exist and have life and have been redeemed] through Him. [Mal 2:10] However, not all [believers] have this knowledge. But some, being accustomed [throughout their lives] to [thinking of] the idol until now [as real and living], still eat food as if it were sacrificed to an idol; and because their conscience is weak, it is defiled (guilty, ashamed).