John Gill Commentary Acts 11:8

"But I said, Not so, Lord: for nothing common or unclean hath ever entered into my mouth." — Acts 11:8 (ASV)

But I said, not so, Lord
For he took the voice he heard to be the voice of the Lord, and yet he was not obedient to the heavenly vision, and even though he was hungry; which shows what a strict observer he was of the ceremonies of the law, and how much he was prejudiced in favour of them:

for nothing common or unclean has at any time entered into my
mouth ;
he had not suffered anything to come within his lips; he had not even tasted, and much less ate anything that was forbidden by the ceremonial law, so strictly had he observed it.