The prophet seems to ask odd questions. If a person carries sanctified meat to used for a sacrifice in his cloak, will that holiness transfer to other objects? No. So if a defiled person touches something holy, will that be defiled? Yes.
Citing such legal issues (Leviticus 6:27; 22:4-6) establishes that defilement is contagious but holiness is not.
What is the point? Apparently the people thought that if they touched holy things – such as the temple, that holiness would transfer to them. Is this the idea behind the empty ritualism that the prophets so routinely denounce? (See Isaiah 1 and Jeremiah 7 for two vivid examples.)
The point seems to be that it is about the heart reflected in the life of the person, not on the external compliance with a rite. What the Lord was seeking was compliance that was the fruit of faith – not compliance designed to cover the lack of faith.
This is similar to Jesus comment in Mark 7:17-23 that it is not what enters someone from the outside, but what arises up from the inside that determines holiness or defilement.
So religion is a poor cover-up. Don’t expect your piety or your charity or your words to hide what is defiled.