Tell that preacher he's a preacher,
A preacher can only teach what he has read. In effect, not his own thoughts. Here Jay is making quite the claim; that his words are born from a much deeper place. Introspection and self examination are what lead him to his world view and beliefs.
Jay draws from James 1:22 King James Version (KJV)
But be ye doers of the word, and not hearers only, deceiving your own selves.
He is basically saying people who are normally quick to be preachy or judgmental of others usually lack substance and they themselves are just as flawed if not more.
He used the similar admonition against false teachings in the past.
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