The reference from Peter's word in 2nd Peter 3:8-9
But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day.
The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.
An accepted book of teaching by many in the early church was the Epistle of Barnabas, attributed to the Barnabas in the Book of Acts.
Of the Sabbath He speaks in the beginning of the creation; And God made the works of His hands in six days, and He ended on the seventh day, and rested on it, and He sanctified it.
"Sanctified" (from the Hebrew word qadesh) means holy, hallowed, separated.
Seen in a bad way with that derived word prostitute in
Seen in a good way in Exodus 3:5. "the place whereon you stand is holy ground"
Thus in Verse 4, Barnabas expands further on the meaning of the Sabbath.
Give heed, children, what this means; He ended in six days. He means this, that in six thousand years the Lord shall bring all things to an end; for the day with Him signifies a thousand years; and this He himself bears me witness, saying; Behold, the day of the Lord shall be as a thousand years. Therefore, children, in six days, that is in six thousand years, everything shall come to an end.
And He rested on the seventh day. this He means; when His Son shall come, and shall abolish the time of the Lawless One, and shall judge the ungodly, and shall change the sun and the moon and the stars, then shall he truly rest on the seventh day.
Barnabas was doubtless familiar with the Lord's words to Enoch in the Second Book of Enoch, a part of the Jewish Apocrypha at the time of the early church.
And I appointed the eighth day also, that the eighth day should be the first-created after my work, and that the first seven revolve in the form of the seventh thousand, and that at the beginning of the eighth thousand there should be a time of not-counting, endless, with neither years nor months nor weeks nor days nor hours.
those last two books aren't part of scripture, they show that the Jews, and early tribes everywhere (even the early Mayans with their recently ended calendar) knew of the prophecies of the Lord's coming, and judgment, and 1,000 year reign
End of Report