The Shepherd of Hermas (c.95–c.150)
[Blessed are] you who endure the great tribulation that is coming on, and [blessed are] they who shall not deny their own life. (Vision 2:2)
Those, therefore, who continue steadfast, and are put through the fire, will be purified by means of it. . . . But the white part is the age that is to come, in which the elect of God will dwell, since those elected by God to eternal life will be spotless and pure…This then is the type of the great tribulation that is to come. (Vision 4:3)