That's great preaching!
St. John the Baptist was the Forerunner of our Lord Jesus Christ.
He preached repentance to all, and though a celibate himself preached especially for the honor of marriage (to Herod and Herodias).
He preached for about 90 days, then was imprisoned and beheaded. You know when they want you dead after only 3 months of preaching, well…
Now that’s great preaching.