GENESIS 2:15
 

[AKJV]

And the LORD God took the man, and put him into the garden of Eden to dress it and to keep it.

[AMP]

So the Lord God took the man [He had made] and settled him in the Garden of Eden to cultivate and keep it.

Please understand these:

The Lord God did not bring the man into the Garden just to enjoy and have fun, eat and rest or play inside the Garden. Rather He brought the man into the Garden basically to Work. 

Purpose

To work, earned Adam entrance into paradise. Adam did not work for it but by grace was he saved or placed into the Garden, but to work. We are not saved by our works but by grace through faith, not of works; however we are saved to work (Good-Works)

[Ephesians 2:8-10] — "For by grace are you saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast. For we are His workmanship, created in Christ Jesus to do good works, which God has before ordained that we should walk in them when saved."

You don't have to work for you to be saved, but you are saved to work out your salvation or bear fruits. Many Christians are lacking in this aspect, and Adam failed in this first assignment of God to him and for which he was brought into the Garden to do.

Supposing I am a poor man looking at a very giant Castle of the rich ruler, with great feast and attractions going on inside there, but I am neither invited nor worthy to go through the gates inside. How do get into that Castle or Organization without trespassing? It's by simply getting hired to do menial but crucial works for them, e.g. Gardening Services, Cleaning Services, House Keeping, etc, even though it's like the lowest grade of work. Is that not the job Adam was employed to do, employed as mere Gardener, Housekeeper, Cleaner, etc for the great Garden of Eden? 

Adam was not employed as Director or higher grade Officer into the Garden, but employed as either Gardener, Gatekeeper or Cleaner, as one of those lower grade of workers in a reputable organization or large household. Eve, the most beautiful Woman on earth married Adam, a man that was a mere Gardener or Garden Keeper, who was neither the owner of the garden nor was he one of the top staff there. Infact, Adam was under rule to not touch or eat something there according to He who employed him; and the penalty for breaking that rule will not just get Adam fired or sacked from there, but will even get Adam to die because of breaking that rule. And Adam agreed to abide by that terms and conditions to work in that Garden or Organization.

Who was that woman that saw the Lord Jesus Christ as a Gardener, and did not even bother to greet Him but even assumed He was the one that stole the Body of Jesus away from the Tomb or He knew where the Body was kept; but as soon as the supposed "Gardener" called her by name, she realized He was the Lord and called Him, "Rabboni?" She looked down at a Gardener.

My illustration is that, for me to get into that large Company, castle or Organization, I should rather seek for those humble work or services to be employed there, just to have access into there. Not seeking the higher grade jobs at first instance. Perhaps, when I am inside there as a mere gardener or cleaner, I could then reapply for upgrade or higher positions there at  vacancies.

In the top Bible verse above, God took and brought the man into the Garden, not because He prepared a table for the man to eat and drink as a feast invitation but, because He was employing the man to do work for Him in His Garden. That is how the Kingdom of God is, as a God or a Man who is recruiting workers into His Garden, Paradise or Vineyard. As it is written,

[Matthew 20:1-2] — "For the kingdom of the heavens is like to a man, a master of a house, who went out in the morning to hire workmen for his vineyard. And having agreed with the workmen on a denarius for the day, he sent them into his vineyard."

Did you see how those laborers or workmen gained access into that man's vineyard through getting hired to work there? That's part of how the Kingdom of Heaven operates in allowing people access. Your works matter, and your works should follow you when you enter, even when your properties would not follow you when you die. You would be amazed at how meticulous our God is, and very Wise in His dealings.

Make yourself relevant in the household of God, and make sure you are employed or offering services that God respects.

Do not see eternity in heaven/earth as just singing and praising God for eternity; for Eternal Life is eternal Rest full of Activities and Works called "Wonders." So there will still be works to do, or doing Wonders and Glorious Deeds for eternity. Ecclesiastes stated that whatever God does is eternal, and man can neither add nor subtract from what God has done and finished (Ecclesiastes 3:15). But to make men relevant in working with God, He chose men to work on whatever He had worked or done. God planted the Garden right? And yet God wanted man to dress and keep it. The Lord said it's finished right? And yet the Lord called men to build on His finished works. God completed the heavens and earth, with the hosts of them on the sixth day right? And yet He called men to replenish the earth and develop it. He made all the animals right? And yet brought them for Adam to name them. He planted the Vineyard as the Owner right? And yet sought workers to work on His Vineyard. 

Later you will understand that God wants men to retouch all the works God created and made including retouching angels, stars, heavenly things, so that all things will come to the state where it will be said of them, "Both God and Men worked them together." Men are God's Coworkers. So bear in mind that your entering into heaven, into paradise etc, is to work and to walk with the Lord in His Household. It's an employment or "High Calling." Those who were faithful in handling their Master's Five Talents were given a higher calling of managing five or ten cities; and those faithful in working two talents were exalted to high calling of working over two cities. Basically, the joys they entered were promotions to working at higher levels over greater things.

The reason I said Adam failed in this first calling of God to man to work in paradise or Garden of God:

I have not seen any scripture that said Adam did or fulfilled those duties of dressing and keeping the Garden. The top Bible verse above only mentioned the Works as Purpose or Calling for Adam into the Garden, but did not mention anywhere else that Adam fulfilled or finished that course/assignment. But in the second assignment given to Adam in the Garden, pertaining to naming the animals, Adam finished that assignment and completed it.

Adam was to dress and keep the Garden, but Adam lost the Garden and obviously did not keep it. A Cherub (angel) and flaming sword was later reassigned or made to replace Adam in the calling of keeping the Garden after Adam was sacked/fired.