SB 7.12.10
kalpayitvatmana yavad
abhasam idam isvarah
dvaitam tavan na viramet
tato hy asya viparyayah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As long as a living entity is not completely self-realized — as long as he is not independent of the misconception of identifying with his body, which is nothing but a reflection of the original body and senses — he cannot be relieved of the conception of duality, which is epitomized by the duality between man and woman. Thus there is every chance that he will fall down because his intelligence is bewildered.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Here is another important warning that a man must save himself from attraction to woman. Until one is self-realized, fully independent of the illusory conception of the material body, the duality of man and woman must undoubtedly continue, but when one is actually self-realized this distinction ceases.
vidya-vinaya-sampanne
brahmane gavi hastini
suni caiva svapake ca
panditah sama-darsinah
“The humble sage, by virtue of true knowledge, sees with equal vision a learned and gentle brahmana, a cow, an elephant, a dog and a dog-eater [outcaste].” (Bg. 5.18) On the spiritual platform, the learned person not only gives up the duality of man and woman, but also gives up the duality of man and animal. This is the test of self-realization. One must realize perfectly that the living being is spirit soul but is tasting various types of material bodies. One may theoretically understand this, but when one has practical realization, then he actually becomes a pandita, one who knows. Until that time, the duality continues, and the conception of man and woman also continues. In this stage, one should be extremely careful about mixing with women. No one should think himself perfect and forget the sastric instruction that one should be very careful about associating even with his daughter, mother or sister, not to speak of other women. Srila Madhvacarya cites the following slokas in this regard:
bahutvenaiva vastunam
yathartha-jñanam ucyate
advaita-jñanam ity etad
dvaita-jñanam tad-anyatha
yatha jñanam tatha vastu
yatha vastus tatha matih
naiva jñanarthayor bhedas
tata ekatva-vedanam
Unity in variety is real knowledge, and therefore giving up variety artificially does not reflect perfect knowledge of monism. According to the acintya-bhedabheda philosophy of Sri Caitanya Mahaprabhu, there are varieties, but all of them constitute one unit. Such knowledge is knowledge of perfect oneness.