The cover picture and the title go hand in hand. The person who goes out and casts seed has in him the hope that the kingdom of God will be expanded. He possesses at minimum, faith the size of a mustard seed. He believes that the all-powerful God whom he serves will release His power in what the picture portrays. The servant of God cast the seed, not knowing but believing that the purposes of God will become evident. Why? Because faith is the substance of things hoped for, the evidence of things not seen (Hebrews 11:1). So in his labors, some seed finds residence in a hard and dark heart of stone. God is working His miracle of regeneration or drawing that hard-hearted individual to Himself. The seed of the eternal Word is cracking and breaking up the hard heart. Sometimes, the person of faith observes something happening. He witnesses what was once a hard and depraved heart is now being softened toward God. If he is involved in up-close evangelism, he is blessed to witness the spiritual miracle of salvation as depicted in the picture as becoming a heart of flesh. That once-hard-hearted person is now able to move in God's direction rather than continuing in his own depraved way. The eternal seed that has been implanted in the heart by God now begins to sprout out with life, demonstrating the life of the Lord Jesus Christ, growing and producing spiritual fruit unto his King; this is his reasonable service.