The serpent was the first New Age salesman. 

Genesis 3:1 KJV Now the serpent was more subtil than any beast of the field which the LORD God had made. And he said unto the woman, Yea, hath God said, Ye shall not eat of every tree of the garden?

Genesis 3:7 KJV And the eyes of them both were opened, and they knew that they were naked; and they sewed fig leaves together, and made themselves aprons.

* Vegan and Masonic nonsense from Adam and Eve to hide their sin. 

Genesis 3:15 KJV And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel.

Jesus is the seed coming from woman, a virgin, who on the cross will bruise the devil's head and the devil will be Jesus' footstool by bruising his heel

God now will demand a blood sacrifice by making garments out of animal skins for them and showing how to kill animals for atonement. Especially cute and innocent lambs because sin hurt God and God wants us to understand this. 

Genesis 3:21 KJV Unto Adam also and to his wife did the LORD God make coats of skins, and clothed them.

Genesis 4:3 KJV And in process of time it came to pass, that Cain brought of the fruit of the ground an offering unto the LORD.

* The Hebrew term for ground is אדמה
'ădâmâh ad-aw-maw'
From H119; soil (from its general redness): - {country} {earth} {ground} husband [-man] ({-ry}) land.

* The Hebrew term for man or Adam is אדם
'âdâm aw-dawm'
From H119; {ruddy} that {is} a human being (an individual or the {species} {mankind} etc.): - X {another} + {hypocrite} + common {sort} X {low} man ({mean} of low {degree}) person.

Genesis 4:5-7 KJV But unto Cain and to his offering he had not respect. And Cain was very wroth, and his countenance fell. 

6. And the LORD said unto Cain, Why art thou wroth? and why is thy countenance fallen? 

7. If thou doest well, shalt thou not be accepted? and if thou doest not well, sin lieth at the door. And unto thee shall be his desire, and thou shalt rule over him.

* Cain didn't offer a blood (more vegan and new age nonsense) sacrifice. This is why his offering was rejected. Cain was also warned by God that his disobedience in not offering a blood sacrifice would let sin lie at his door and the LORD would not pass-over him by overlooking Cain's sin. 

No need for new age because the devil's counterfeit will never be able to reach the depths of Genesis, not to mention the rest of the Bible. And yes it is an inside job by the very nature of the sons and daughters of Adam who seek to manufacturer solutions that are counterfeit to sin and only produce more sin.