Nephilim

The angels that left their abode are the ones that influenced man to sin. They were not the ones that went into the daughters of men.

1. Genesis 6:1-4: This passage mentions the "sons of God" who married the "daughters of men," which led to the birth of the Nephilim, described as "heroes of old, men of renown." The identity of these "sons of God" has been debated among scholars. Some interpret them as fallen angels, others as descendants of Seth (representing the lineage of the faithful), and still others as powerful rulers or kings who took multiple wives.

2. Book of Enoch: This is an ancient Jewish religious work, traditionally ascribed to Enoch, the great-grandfather of Noah. The Book of Enoch is not included in the biblical canon used by most branches of Judaism or Christianity, except the Ethiopian Orthodox Church. It elaborates greatly on the brief Genesis story, detailing how 200 "Watchers" (a class of angels) descended to Earth on Mount Hermon, took human wives, and taught humanity various forbidden arts. This act leads to the corruption of mankind and the earth, which becomes one of the reasons for the Great Flood. Enoch describes these angels as being punished by God for their disobedience.

3. Theological Interpretation: In broader Christian theology, there is also a narrative about angels who rebelled against God and were cast out of Heaven. This is often associated with Lucifer (Satan), but the specifics can vary widely among different traditions and texts. The concept of fallen angels influencing mankind towards sin is part of this broader narrative, linked more explicitly in later interpretations and texts like the Book of Enoch rather than directly in Genesis.

In summary, the narrative about angels that left their proper dwelling to influence humanity covers different interpretations and expansions beyond the initial Genesis account. The idea that these beings taught mankind various sinful practices and thereby increased human wickedness on Earth, leading to God's decision to send the Flood, is more fully developed in the Book of Enoch and other pseudepigraphal texts rather than the canonical Bible.