The Tree of the Knowledge of Good and Evil (TKGE) could also be called the following:
THE TREE OF LAW. Paul indicated in 2 Cor 11:2b-3 that to go back to living under the mosaic law is like Adam and Eve being tricked into eating from the TKGE. This tree makes you a performance-based thinker and causes its eaters to view God and others legalistically. We begin to believe that this is the way God treats us and we should treat others. It leads to eye for eye and tit for tat legal relationships. One cannot love or forgive unconditionally. One cannot understand grace or undeserved favor. One can't believe that God is kind to both the evil and the good. Lk 6:35.
THE TREE OF JEWISH RELIGION. Jesus found no fruit on the fig tree, cursed it and caused it to wither away in Matt 21:17-22. The fig tree here represents the Jewish law and religion. Religion/law can never nourish, heal or give us life. Religion is always a system of gaining reward or avoiding punishment based on our own performance. But these are both selfish motives. The problem with religion is that it can never transform the inner self.
People who eat from the Tree of Religion are always legalistic, judgmental and self-righteous. For an example of this look at the first few verses of John 9 where Jesus' disciples saw the blind man and immediately attributed his blindness to his own sin or that of his parents. See Ex 20:5. Christianity is based on Christ's performance, not ours.