That is Old Testament teaching, Logic1. The New Testament changes things, as shown by Matthew 15.
10And he called the multitude, and said unto them, Hear, and understand:
11Not that which goeth into the mouth defileth a man; but that which cometh out of the mouth, this defileth a man.
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16And Jesus said, Are ye also yet without understanding?
17Do not ye yet understand, that whatsoever entereth in at the mouth goeth into the belly, and is cast out into the draught?
18But those things which proceed out of the mouth come forth from the heart; and they defile the man.