If I partake with thankfulness, why am I evil spoken of for that for which I give thanks?

But if I give praise to God for the food which I take, let no man say evil of me for that reason.

Και εαν εγω μετ' ευχαριστιας μετεχω, δια τι βλασφημουμαι δι' εκεινο, δια το οποιον εγω ευχαριστω;

For if I by grace be a partaker, why am I evil spoken of for that for which I give thanks?