For the herald of the gospel to be spiritually out of order in his own proper person is, both to himself and to his work, a most serious calamity; and yet, my brethren, how easily is such an evil produced, and with what watchfulness must it be guarded against!… It is a terrible thing when the healing balm loses its efficacy through the blunderer who admisters it. You all know the injurious effects frequently produced upon water through flowing along leaden pipes; even so the gospel itself in flowing through men who are spiritually unhealthy, may be debased until it grow injurious to their hearers… Moreover, when a preacher is poor in grace, any lasting good which may be the result of his ministry, will usually be feeble and utterly out of proportion with what might have been expected. Much sowing will be followed by little reaping; the interest upon the talents will be inappreciably small. In two or three of the battles which were lost in the late American war, the result is said to have been due to the bad gunpowder which was served out by certain “shoddy” contractors to the army, so that the due effect of a cannonade was not produced. So it may with us. We may miss our mark, lose our end and aim, and waste our time, through not possesing true vital force within ourselves, or not possesing it in such a degree that God could consitently bless us. Beware of being “shoddy” preachers.
Lectures to My Students (Pasadena, TX; Pilgrim; 1990) p. 2-3