HOW LONG DID IT TAKE FOR ADAM TO FALL? DID IT HAPPEN IMMEDIATELY AFTER CREATION OR MUCH LATER?
We do not have any text that specifies as to how long after creation our first parents fell. But a careful analysis of the fall indicates it was not long after creation.
The very fact God that instructed Adam of the test on the day of his creation shows that the tempter was around, and that the temptation was not far away. We have no record of Adam and Eve doing anything after creation, though they would have gone around and enjoyed God's nature, and would have started to work in the Garden, for God commanded the man, the day he was made:
To dress it and to keep it. (Genesis 2:15)
Adam named all the animals in the Garden the day he was created, even before Eve was brought forth. Interestingly, we see, Adam naming his wife, "Eve", in Genesis 3:20, after the Bible talks of their fall. So this should indicate, at least, that the fall was not long after they were created.
From the tempter's point of view, he would have liked to have had a go at them earlier than later, for the more he delays the more they would have known the loving character and truth of God, and that extra knowledge would be a tougher barricade for him to break through.
While making them on the sixth day, God said:
Be fruitful, and multiply, and replenish the earth, and subdue it. (Genesis 1:28)
The blessing for them to bear children was given while they were sinless. So they could bear children even while they were sinless, for God made them "male and female". But it was only after the test Eve bore children. The Bible says:
And Adam knew Eve his wife; and she conceived, and bare Cain, and said, I have gotten a man from the LORD. (Genesis 4:1)
There are some who try to suggest that they could not have had children if they did not sin. This is untrue, as we have already seen God giving them the command to bear children and fill the earth even before they fell.
You will see in God's message to Eve, after the fall, that He indicated a change of the original experience in child bearing.
Unto the woman he said, I will greatly multiply thy sorrow and thy conception; in sorrow thou shalt bring forth children; and thy desire shall be to thy husband, and he shall rule over thee. (Genesis 3:16)
The Phrase, "I will greatly multiply thy sorrow and thy conception" clearly shows that she would not have had this painful experience had she not fallen in sin.
Initially, Adam was appointed ruler of this planet, Eve was to share the rule with him. But after sin, her husband would rule over her, and the reign of the earth passed on from Adam to Satan, his conqueror. (See Genesis 3:16; Luke 4:5, 6). Also the original plan of child bearing took a beating.
It is most likely that God wanted them to face the test and then reproduce; otherwise what would their child be, if he were born before the test? If they passed the test it would be fine, and if they would fail the test (which they did,) what would be the fate of a sinless, holy and perfect child? So the test was first, before they could set up a family. Therefore, we logically can conclude, it was not long after creation that our first parents fell into sin.