The Book of Yoga (Book Seven) is tracing Savitri’s journey of yoga. She has found her soul and all her centres have bloomed. She has opened herself to the Cosmic Powers and the Force of the Divine Mother has awakened in her. But she has not come only for an individual realisation. She has come to open the doors to a new possibility that is not yet there in the manifested creation so far. She shoots up to the Transcendent beyond the individual and the cosmos.
But before she can go into the Beyond, beyond Time and Space and creation itself, beyond all manifestation, she confronts the dark inconscient base that is not willing to concede this grand escape into the Absolute. It challenges her as the Voice of Night opening doors to a tremendous fear, the original fear of annihilation that pulls man’s soul towards the abyss. She must confront this shadow of the Absolute before she can find her way to the Ultimate Reality. The Voice of the Light invades her being to guide her. Awakened fully and prepared by the Voice of the Light Savitri begins to still herself and enter the Silence of the Absolute.
She completely annuls herself and with the death of the ego-self she is able to climb towards the Supreme Mystery that is beyond all description and definition, the Absolute, the Sole Reality, the Truth that casts no shadow.
About Savitri | B1C3-11 Towards Unity with God (pp.31-33)