Srila Prabhupada would often quote Srila Bhaktisiddhanta who said, “One who has life, preaches.”
Preaching is our life. If one is not preaching Krsna consciousness, speaking about Krsna, and hearing about Krsna, he does not feel like he has any life.
Caitanya Caritamrita Lectures Book, Madhya Lila, Pg 293