Without extended, concentrated prayer, the ministry of the Word withers. And when the ministry of the Word declines, faith (Rom. 10:17; Gal. 3:2, 5) and holiness (John 17:17) decline. Activity may continue, but life and power and fruitfulness fade away. Therefore, whatever opposes prayer opposes the whole work of ministry.

Brothers, We Are Not Professionals: A Plea to Pastors for Radical Ministry (ed. 2013)