This external energy of the Lord covers up the pure knowledge of the living entities eternally existing with Him, but the covering is so constant that it appears that the conditioned soul is eternally ignorant
SB Canto 2
These three modes of material nature, being further manifested as matter, knowledge and activities, put the eternally transcendental living entity under conditions of cause and effect and make him responsible for such activities.
Because they are between the internal and external potencies, the eternally transcendental living entities are called the marginal potency of the Lord. Factually, the living entities are not meant to be so conditioned by material energy, but due to their being affected by the false sense of lording it over the material energy, they come under the influence of such potency and thus become conditioned by the three modes of material nature. This external energy of the Lord covers up the pure knowledge of the living entities eternally existing with Him, but the covering is so constant that it appears that the conditioned soul is eternally ignorant. Such is the wonderful action of māyā, or external energy manifested as if materially produced. By the covering power of the material energy, the material scientist cannot look beyond the material causes, but factually, behind the material manifestations, there are adhibhūta, adhyātma and adhidaiva actions, which the conditioned soul in the mode of ignorance cannot see. The adhibhūta manifestation entails repetitions of births and deaths with old age and diseases, the adhyātma manifestation conditions the spirit soul, and the adhidaiva manifestation is the controlling system. These are the material manifestations of cause and effect and the sense of responsibility of the conditioned actors. They are, after all, manifestations of the conditioned state, and the human being's freedom from such a conditioned state is the highest perfectional attainment.