they committed spiritual iniquity in the form of: yoga, occultism, esotericism, idolatry, unclean/unholy creeds/cults, transcendental meditation, astrology, etc., because in that time there was a very great spiritual iniquity, and therefore there were many powerful avatars, yogis, occultists, sorcerers, etc. - namely they were the so-called fallen "sons of God" and "giants"(nephilim) shown in Genesis 6th chapter, such as krishna and the rest of this kind
Genesis 6:1-6 "And it came to pass, when men began to multiply on the face of the earth, and daughters were born unto them(i.e. and they found creeds), That the sons of God saw the daughters of men that they were(i.e. and the earthly clerics found that the human(666) creeds seemed to be ostensibly) fair; and(i.e. and then) they took them wives(i.e. doctrines) of all which they chose. And(i.e. and for that reason) the LORD said, My spirit shall not always strive with man, for that he also is flesh(i.e. for its spiritual/religious iniquity rises/multiplies): yet his days shall be an hundred and twenty years. There were giants(i.e. the nephilims, viz. greatest clerics of the "darkness" - the ancient yogis/avatars) in the earth in those days; and also after that, when the sons of God came in unto the daughters of men(i.e. when the earthly clerics followed the human creeds), and they bare children(i.e. spiritual children) to them, the same became mighty men(i.e. the same became spiritual giants of universal scale) which were of old, men of renown(i.e. the gigantic clerics of (the) human(666) glory). And God saw that the wickedness(i.e. that the spiritual/religious iniquity) of man was great in the earth, and that every imagination of the thoughts of his heart(i.e. of its faith) was only evil continually. And it repented the LORD that he had made man on the earth, and it grieved him at his heart."
after the flood in the time of Noah God gave the land of the nephilim to the ammonites in order to sanctify it, and that land covers the region of the himalayas and india, so the present natives of india and the himalayas are more or less descendants of the then ammonites, because most of the ammonites were idolaters who like to follow after the tradition(s) of the ancient avatars, yogis and brahmins, while only a small number of them were really righteous before the true Lord God - Jesus even called such people "lilies"(Matthew 6:28-30), because despite their paucity they were righteous
Deuteronomy 2:17-21 "That the LORD spake unto me, saying, Thou art to pass over through Ar, the coast of Moab, this day: And when thou comest nigh over against the children of Ammon, distress them not, nor meddle with them: for I will not give thee of the land of the children of Ammon any possession; because I have given it unto the children of Lot for a possession. (That also was accounted a land of giants: giants dwelt therein in old time; and the Ammonites call them Zamzummims; A people great, and many, and tall, as the Anakims; but the LORD destroyed them before them; and they succeeded them, and dwelt in their stead:"
Blessings