Dante's Inferno - Canto IV - Sadness and Triumph

The Poet, being roused by a clap of thunder, and following his guide onward, descends into Limbo, which is the first circle of Hell, where he finds the souls of those, who although they have lived virtuously and have not to suffer for great sins, nevertheless, through lack of baptism, merit not the bliss of Paradise. Hence he is led on by Virgil to descend into the second circle.