Is it possible to distinguish the moment when one attains perfect concentration from the moment when, starting from this concentration, one opens oneself to the universal Energy?
Yes. You concentrate on something or simply you gather yourself together as much as is possible for you and when you attain a kind of perfection in concentration, if you can sustain this perfection for a sufficiently long time, then a door opens and you pass beyond the limit of your ordinary consciousness—you enter into a deeper and higher knowledge. Or you go within. Then you may experience a kind of dazzling light, an inner wonder, a beatitude, a complete knowledge, a total silence. There are, of course, many possibilities but the phenomenon is always the same.
To have this experience all depends upon your capacity to maintain your concentration sufficiently long at its highest point of perfection.
[The Mother: CWM 4]