True Parents have absolute and eternal love. But we inherited the wrong root of love through the fall. But love, in the beginning of mankind, started in the wrong direction. Without recognizing this, then salvation and a religious life become meaningless. Mankind, represented by a tree, has multiplied fallen nature throughout the world.
Fallen man exists only as a shell.
He must receive love and become one with the parents. Before finding new life, there has to be love. Most Christianity emphasizes Jesus' blood. That is why the goal in the Old Testament was to have the Marriage of the Lamb. They are born and become mature physically, but in essence they have not been truly born.