Here the word avidyā is very significant. Avidyā means forgetfulness of one's identity. Every one of us is a spirit soul, but we have forgotten. We think, "I am this body." This is called avidyā. Saṁśaya-granthi means "doubtfulness." The knot of doubtfulness is tied when the soul identifies with the material world. That knot is also called ahaṅkāra, the junction of matter and spirit. By proper knowledge received from the scriptures in disciplic succession and by proper application of that knowledge, one can free himself from this binding combination of matter and spirit. Brahmā assures Devahūti that her son will enlighten her, and after enlightening her He will travel all over the world, distributing the system of Sāṅkhya philosophy.
The word saṁśaya means "doubtful knowledge." Speculative and pseudo yogic knowledge is all doubtful. At the present moment the so-called yoga system is prosecuted on the understanding that by agitation of the different stations of the bodily construction one can find that he is God. The mental speculators think similarly, but they are all doubtful. Real knowledge is expounded in Bhagavad-gītā: "Just become Kṛṣṇa conscious. Just worship Kṛṣṇa and become a devotee of Kṛṣṇa." That is real knowledge, and anyone who follows that system becomes perfect without a doubt.