A clear and vigorous challenge to preachers and laymen to remain persistent in sharing the gospel with unsaved people. The book is split in two parts:

1. The promise of duty. How does Christ make men ‘fishers of men’? Why are unconverted men compared to fish under water? In what ways are ministers fishers by office?
   
2. How may I come by this art? What following Christ supposes and implies? In which way is Christ to be followed?
   This is a classic explanation of the Puritan approach to evangelism that is also an encouragement for anyone explaining the gospel to someone else.