THE STRAIT GATE OR, GREAT DIFFICULTY OF GOING TO HEAVEN: By: John Bunyan.

http://www.reformed.org/master/index.html?mainframe=/books/bunyan/the_strait_gate.html

Plainly proving, by the Scripture, that not only the Rude and Profane, but many great Professors, will come short of that Kingdom.

“Enter ye in at the strait gate; for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat: because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.” — Matthew 7:13, 14.