Genesis 3 explains how sin came into the world but does not patently state why God allowed Satan into the Garden of Eden. However, a viable answer is discernable in God’s plan of salvation.
The Genesis narrative reveals that God created Adam and Eve—the first man and woman of the human race. They were made perfect and sinless, and God gave them everything they needed to enjoy and thrive. He did all this out of His fathomless, unconditional love for them. God desired them to love Him in return and express that love through faithful obedience.
For love to be proved genuine, God gave Adam and Eve and all succeeding people the freedom to choose. We can choose to love or not to love, to obey God or not to obey Him, to do good or evil. If the human will had never been allowed to be tested and proved, then people would be nothing more than robots. God could have created us to love and obey Him automatically. He could have put a fence around the Garden of Even and never allowed humanity to be tempted. But God’s desire was and is for people to love Him sincerely, obey Him willingly, and worship Him wholeheartedly (Deuteronomy 10:12–13; Matthew 22:37; John 14:15; 1 John 4:19).
God placed a restriction on Adam and Eve. He commanded, “You are free to eat from any tree in the garden; but you must not eat from the tree of the knowledge of good and evil, for when you eat from it you will certainly die” (Genesis 2:16–17). The tree was God’s test of obedience and love.
Even though Adam and Eve were in paradise without sin, rebellion and evil had already come into creation through the angel Lucifer’s fall (Isaiah 14:12–15). Lucifer was created perfect and beautiful and may have been in the Garden of Eden prior to his rebellion (see Ezekiel 28:13). Lucifer’s undoing was his proud desire to “be like the Most High” (Isaiah 14:14, NLT). After his fall, Lucifer became known as Satan or the devil. Evil and sin came into the world through Lucifer’s rebellion.
Satan lured Eve with the same sin he had committed—the ambition to be like God (Genesis 3:4–5). Both the tree and Satan presented a test. Eve took Satan’s bait, Adam chose to follow Eve into sin, and the fall of humankind was complete (Romans 5:12). The couple and all subsequent humans would pay the consequences of their disobedience, beginning with separation from God. Sin breaks our fellowship with God. Born in a state of estrangement from our Creator, we all desperately need a Savior to reconcile and restore our relationship with God (Romans 3:9, 10–12, 23; Psalm 51:5; Ephesians 2:3).
Why did God allow Satan to enter the Garden of Eden? At best, we can speculate that God allowed it as a means of testing Adam and Eve’s love and obedience. Why did God let His beloved creations fall into sin? These questions have no definitive answers in Scripture. The Bible does not tell us everything we want to know, but God, through His Word, does provide everything we need (2 Timothy 3:16–17; 2 Peter 1:3). We can stand firm on the truth Scripture does reveal. We know God is good, wise, and loving (Luke 18:19; Genesis 50:20; 1 John 4:8, 16). Everything He does is in our best interest, for a good and loving purpose (Romans 8:28; 31–38).
Some things are hidden from us in Scripture and not for us to know: “The secret things belong to the Lord our God, but the things revealed belong to us and to our children forever, that we may follow all the words of this law” (Deuteronomy 29:29). We are allowed to explore, research, and discover much in God’s Word, but there is infinite knowledge beyond our finite reach (Psalm 44:21; Daniel 8:26; Romans 11:33; 16:25). When we are left with unanswerable questions, we must be willing to accept what God has not revealed and cling to what He has.