In the Bible, eating represents taking in knowledge and the desire for good. Trees represent knowledge and understanding that come from the Lord. So this verse says the people of the Most Ancient Church – "man" or "Adam" – were free to gather the knowledge that flowed to them from the Lord.

This happened in a way that we cannot truly understand now. Because the people of the Most Ancient Church were in a state of love to the Lord, they know instantly, from their affections, what was true. They didn't have to ponder logic and ask questions; they simply knew from their emotional response whether an idea was in accord with love to the Lord.

(Odkazy: Arcana Coelestia 0125)

296. The first and foremost duty of a church is to know and acknowledge its God, since without this knowledge and acknowledgment there can be no joining with God. In the Christian church, then, there is no joining with God without acknowledgment of the Lord. The Lord tells us this in John:

Those who believe in the Son have eternal life. Those who do not believe in the Son will not see life; instead, the wrath of God abides on them. (John 3:36)

And elsewhere,

If you do not believe that I am, you will die in your sins. (John 8:24)