Barnabas, Epistle of Barnabas 15

It is also written about the Sabbath in the ten words which God spoke face to face with Moses on Mount Sinai: "You shall sanctify the Sabbath of the Lord with clean hands and a clean heart" (Exod 20:8–11). Elsewhere it says: "If my sons keep the Sabbath, then I will put my mercy upon them" (Exod 31:13). At the beginning of creation the Sabbath declares: "And God made the works of his hands in six days, and he finished on the seventh day and rested on it and sanctified it" (Exod 20:8–11). Children, pay attention to what "he finished in six days" means. It means that in six thousand years the Lord will finish all things, for with him a day signifies a thousand years. He himself testifies to me, saying, "Behold, the day of the Lord will be as a thousand years" (Ps 90:4). So then, children, in six days—that is, in six thousand years—all things will be finished. "And he rested on the seventh day." This means: when his Son comes and destroys the reign of the lawless one, judges the ungodly, and changes the sun, the moon, and the stars, then he will truly rest on the seventh day. For it says: "You shall sanctify it with clean hands and a clean heart." If anyone can now sanctify the day which God sanctified while being clean in heart, we have all gone astray. Understand, then, that we will sanctify it by resting properly only when we ourselves have been justified and have received the promise, when lawlessness is no more and all things have been made new by the Lord; then we will be able to sanctify it, having first been sanctified ourselves. For he says to them: "Your new moons and your Sabbaths I cannot endure" (Isa 1:13). See how he speaks: the present Sabbaths are not acceptable to me, but the one I have made, in which, after I have rested, I will make the beginning of the eighth day, which is the beginning of another world. That is why we also keep the eighth day with joy—the day on which Jesus rose from the dead, appeared, and ascended into the heavens.