According to Osho, true transmission in a lecture is nonverbal: words only engage your mind so your heart becomes available. The real work happens through the master's presence and silence, on a level deeper than thought, dissolving egoic resistance. Depending on your openness, this catalytic energy can be gentle or shattering, operating to annihilate the old and allow a rebirth of being.
He talks to keep your mind busy so his silent presence can reach your heart and help the hard ‘me’ soften and change.