The Cost of Neglecting Illumination

Preachers who respond to the Spirit's insights into God's Word and who faithfully proclaim God's message can expect to receive more of the Spirit's light. Present obedience to illumination procures future illumination. The opposite is also true: If you do not respond to the Spirit's illumination because sin has darkened your heart, then less light is given. So do not neglect the light the Spirit gives you.

-- Greg Heisler, Spirit-Led Preaching, p.50