It is therefore clearly established that motion, whether advancing or declining, is necessary to existence. Now, as the human spirit continues after death, it must either advance or decline, and in the next world to cease to advance is the same as to decline. But the human spirit never transcends its own degree: It progresses only within that degree. For example, no matter how far the spirit and reality of Peter may progress, it will never reach the degree of the reality of Christ but will progress only within its own inherent limits.
Thus, you see that however much this mineral may progress, its progress remains within its own degree; you cannot possibly bring this crystal, for example, to a state where it gains the power of sight. The moon, howsoever it may progress, can never become the shining sun, and its apogee and perigee will always remain within its own degree. And however far the Apostles might have progressed, they could never have become Christ. It is true that coal can become a diamond, but both are in the mineral degree and their constituent parts are the same.
- ‘Abdu’l-Baha (Table talks in Akka, authenticated by ‘Abdu’l-Baha; ‘Some Answered Questions’ – 2014 revised translation by the Baha’i World Centre)
