Christian doctrines live and bear fruit only while connected to the Vine, Jesus Christ.
John 15:1, 2
"I am the true vine, and my Father is the gardener. He cuts off every branch in me that bears no fruit, while every branch that does bear fruit he prunes so that it will be even more fruitful."
This book explains the sum of the everlasting gospel. All biblical truths must be proclaimed in the light of the Gospel.