William Barclay once wrote, "The preaching on Pentecost finished with the statement that in Jesus alone was salvation; that he who believed on Him would receive the Holy Spirit and that He who would not believe was destined for terrible things.  That is to say, it finished with both a promise and a threat.  It is exactly like that voice which Bunyan heard in "Pilgrim's Progress", namely, 'Wilt thou leave thy sins and go to heaven, or wilt thou have thy sins and go to Hell.'"