Irenaeus
2. Thus, then, in the day that they ate, in the same did they die, and became death's debtors, since it was one day of the creation. For it is said, There was made in the evening, and there was made in the morning, one day. Now in this same day that they ate, in that also did they die. But according to the cycle and progress of the days, after which one is termed first, another second, and another third, if anybody seeks diligently to learn upon what day out of the seven it was that
Adam died, he will find it by examining the dispensation of the Lord. For by summing up in Himself the whole
human race from the beginning to the end, He has also summed up its death. From this it is clear that the Lord suffered death, in
obedience to His Father, upon that day on which
Adam died while he disobeyed God. Now he died on the same day in which he ate. For God said, In that day on which you shall eat of it, you shall die by death. The Lord, therefore, recapitulating in Himself this day, underwent His sufferings upon the day preceding the
Sabbath, that is, the sixth day of the creation, on which day man was created; thus granting him a second creation by means of His
passion, which is that [creation] out of death. And there are some, again, who relegate the death of
Adam to the thousandth year; for since a day of the Lord is as a thousand years,
2 Peter 3:8 he did not overstep the thousand years, but died within them, thus bearing out the sentence of his
sin. Whether, therefore, with respect to disobedience, which is death; whether [we consider] that, on account of that, they were delivered over to death, and made debtors to it; whether with respect to [the fact that on] one and the same day on which they ate they also died (for it is one day of the creation); whether [we regard this point], that, with respect to this cycle of days, they died on the day in which they did also eat, that is, the day of the preparation, which is termed the pure supper, that is, the sixth day of the feast, which the Lord also exhibited when He suffered on that day; or whether [we reflect] that he (Adam) did not overstep the thousand years, but died within their limit — it follows that, in regard to all these significations, God is indeed
true. For they died who tasted of the tree; and the serpent is
proved a liar and a murderer, as the Lord said of him: For he is a murderer from the beginning, and the
truth is not in him.
John 8:44
When the Lord said it was good or very good he was saying it was exactly the way he planned creation. Another way of saying it t was a time without sin when he said it. Since it was one of the Lord's feasts it had to be the Feast of Unleaven Bread. A seven day feast.
And the sixth day was the original Passover, the day the Lord took animals and made clothing for Adam and Eve. it was the beginning of a blood sacrifice for sins!