"A minister of Christ should be thoroughly furnished unto all good works. You have made a miserable failure. You must show in your family that kindly consideration, that tenderness, love, gentleness, noble forbearance, and true courtesy, that is becoming to the head of a family, before you can make a success of winning souls to Christ. If you have not wisdom to manage the small number with whom you are closely united, how can you make a success of managing a larger company, who are not especially interested in yourself? Your wife needs to be truly and thoroughly converted to God. Neither of you are in a condition to correctly represent our faith. You both need a thorough conversion. 3T 556.1"
"That the man of God may be perfect, throughly furnished unto all good works."
The phrase "thoroughly furnished unto all good works" is a direct quote from 2 Timothy 3:17. The EGW passage uses this concept in the context of a minister's qualifications.