Genesis8:3

It appears that the number 150 was another way to communicate completeness in ancient times, possibly because it three units of 50. Sometimes soldiers were divided into units of 50 rather than 100, and then combined as desired. Hebrews society was organized in such a way that certain men were over 100 other men, other were over 50, and others over 10 men. The number three was usually a symbol of completeness, thus three times fifty was completeness on a large scale.

Therefore, this verse communicates that the waters were strong and prevailed completely; no one was able to successfully resist them. By the 150^th day, the water had already accomplished its purpose and was obviously receding. It had successfully proven that it was victorious.

Genesis 8:2 makes it sound like the sources that can open and close (the window lattices and the springs or eyes) were closed quickly and totally. I have become convinced that the point being made here is that the progression of the flood changed course and the waters began to recede instead of increasing. That is all we can be sure of. These two verses could mean that the rains subsided noticeably, but it still rained some. This would represent God partially closing the window lattices of the heavens because the evaporation was still intense due to overheated oceans. Or it could mean that God restrained the rain altogether and held it till after the flood when it helped start an ice age (He totally closed the lattices). I prefer the second option, that God stopped the rain from this point till the end of the flood event.

If the closing of the windows of heaven, i.e. the stoppage or the rain, happened at a specific point in time, it happened prior to day 150 of the flood, but we are not told exactly which day. Noah probably tried to record all this info, but since the rain had come and gone since day 40, it is possible that he stopped recording the presence or absence of rain. Later he realized, “Hey, it hasn’t rained at all for a number of days now. Something has changed.” By day 150 he was convinced that the water was receding.

The conditions for continued, heavy rains were still present, but it appears from these two verses that God intervened to restrict all rain from that point till the end of the flood event.

Evaporation was still at high levels because the seas were still much hotter than they are today, close to 47 degrees hotter. God appears to have been holding back the rain, just as He did before the flood started. I believe He held the rain in reserve for a short ice age of about 700 – 800 years. So here we have a second time that God controlled the amount of rain coming on the earth just as the ancients would open or close their window lattices, shutters or louvers, to control how much sunlight (and heat) came into their homes.

He could have taken soundings, or he may have had a visual reference point by then.

If Greater Ararat had already erupted sufficiently to become a tall mountain, and if the water had gone down enough to expose Greater Ararat, and if the ark was close to Greater Ararat, then Noah could have watched the water level go down compared with the top of its peak. This assumes that, despite the strong winds He had sent, God kept the ark close to Mount Ararat during the time of receding water, so Noah could have a consistent reference point with which to gauge how far the waters had gone down.

The stone cores collected by the oil drilling companies indicate that runaway subduction continued until the very end of the flood event. So the statements in Genesis 8:2 & 3 serve to tell us that the flood event changed course; the volume of ocean floor that was already in place and cooling surpassed the volume of hot ocean floor that was being created by runaway subduction. This resulted in a smaller portion of the sea floor that was lifted up, and if the average level of the sea floor lowered, it would result in the average level of the sea on the surface also being lowered. So the statement of the eyes of the abyss being closed is true, but it must be qualified.   This valve was closed slowly, whereas the valve controlling the rain may have been closed rather quickly, we cannot say for sure.