What did early Christians believe about...?

Uninspired records of how early Christians worshipped and what doctrine they believed!

120-205 AD Irenaeus "Christ will not die again on behalf of those who now commit sin because death shall no more have dominion over Him.... Therefore we should not be puffed up.... But we should beware lest somehow, after [we have come to] the knowledge of Christ, if we do things displeasing to God, we obtain no further forgiveness of sins but rather be shut out from His kingdom" (Heb. 6:46). (Irenaeus, pupil of Polycarp, Against Heresies bk. 4, chap. 27, sec. 2)
140-230 AD Tertullian "Some people act as though God were under an obligation to bestow even on the unworthy His intended gift. They turn His liberality into slavery.... For do not many afterwards fall out of grace? Is not this gift taken away from many?" (Tertullian On Repentance chap. 6.)
200-258 AD Cyprian "It is written, 'He who endures to the end, the same shall be saved' [Matt. 10:22]. So whatever precedes the end is only a step by which we ascend to the summit of salvation. It is not the final point wherein we have already gained the full result of the ascent." (Cyprian Unity of the Church sec. 21)