Eusebius mentions the Didache as an accepted document in early Christianity. He (or other leading Christians) does not believe it is a canonical book but that it did give some value. As such, the Didache gives insight as to how the Christians around the time of Eusebius understood the Bible. The Didache styles itself as the teachings of the twelve apostles on how to live as a Christian. It gives commands on how to live morally, including exclusion of abortion. Although it is short on statements about God or other Scriptures, it does give a sense of the daily operations of Christian life. The command was to be righteous.
As in other early Christian texts, there was an implicit understanding of works-salvation:
Do not in any way forsake the commandments of the Lord; but keep what you have received, neither adding thereto nor taking away therefrom. In the church you shall acknowledge your transgressions, and you shall not come near for your prayer with an evil conscience. This is the way of life.
And the way of death is this: First of all it is evil and accursed: murders, adultery, lust, fornication, thefts, idolatries…
…See that no one causes you to err from this way of the Teaching, since apart from God it teaches you. For if you are able to bear the entire yoke of the Lord, you will be perfect; but if you are not able to do this, do what you are able.
This document is warning against antinomians, those who preach a faith-alone salvation. It could be understood as warning against the Nicolaitans, but the document just does not have a faith-alone tone.
The author also believes the audience is still in the end of days, that the end of the world was imminent, that individuals could lose their salvation, and that not all people would rise from the dead:
Let not your lamps be quenched, nor your loins unloosed; but be ready, for you know not the hour in which our Lord will come. But come together often, seeking the things which are befitting to your souls: for the whole time of your faith will not profit you, if you are not made perfect in the last time… but those who endure in their faith shall be saved from under the curse itself. And then shall appear the signs of the truth: first, the sign of an outspreading in heaven, then the sign of the sound of the trumpet. And third, the resurrection of the dead — yet not of all, but as it is said: “The Lord shall come and all His saints with Him.” Then shall the world see the Lord coming upon the clouds of heaven.
As an interesting end note, this document also suggests a figurative interpretation of the Eucharist.