The real question is: How powerful is the Word of God? Can it change men from sinners into saints without an extension of an altar call? Will it convict and convert (as God promises), or will we need to add something that helps men “settle it”? You will never be able to do without the invitation system until you are thoroughly convinced of the power of God's Word (see Rom. 10:14; Jas. 1:18; 1 Pet. 1:23).