The following poem, Aaron, by English country parson, George Herbert, describes beautifully the necessary preparation of a preacher:
Holiness on the head,
Light and perfection on the breast,
Harmonious bells below, raising the dead
To led them unto life and rest.
Thus are true Aarons dressed.
Profaneness in my head,
Defects and darkness in my breast,
A noise of passions ringing me for dead
Unto a place where is no rest.
Poor priest thus am I dressed.
Only another head
I have, another heart and breast,
another music, making live not dead,
without whom I could have no rest:
In him I am well dressed.
Christ is my only head,
My alone only heart and breast,
My only music, striking me even dead;
That to the old man I may rest,
And be in him new dressed.
So holy in my head,
Perfect and light in my dear breast,
My doctrine tuned by Christ, (who is not dead,
But lives in me while I do rest)
Come people; Aaron's dressed