Titus 1:15

‘To the pure all things are pure, but to those who are defiled and unbelieving nothing is pure, but both their mind and their conscience are defiled.’

‘To the pure all things are pure’ may have been a proverb, but it may have been coined by Paul on the basis of Jesus’ teaching in Mark 7:15; Mark 7:18-19; compare Romans 14:20. The point is that true purity is of the heart. And as long as the heart is pure then nothing can defile a man. That is why Jesus was never defiled when he touched a leper, or someone who was unclean, in order to heal them. He was totally pure. And those who have been made pure in the blood of Christ also cannot now be defiled by ‘things’. On the other hand if the heart is defiled and unbelieving (not truly believing in Jesus Christ) then nothing is pure whatever ordinances they go through (compare Isaiah 1:11-17). Even their mind and consciences are defiled so that they can neither understand or judge what is right.

Alternatively it is possible that ‘To the pure all things are pure’ was cited by the false teachers, on the grounds that having been purified by their ceremonies, rites and gaining of knowledge they could then do what they liked, because having been made pure in spirit nothing in the flesh could defile them. If so Paul’s reply is clear. To those who are defiled and unbelieving nothing is pure.