(King James translation)
And it came to pass, when men began to multiply on the face of the earth, and daughters were born unto them, that the sons of God saw the daughters of men that they were fair; and they took them wives of all which they chose. And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years. There were giants in the earth in those days; and also after that, when the sons of God came in unto the daughters of men, and they bare children to them, the same became mighty men which were of old, men of renown.
As you have said, as a Muslim you must as a matter of dogma 'believe' in the Old Testament. Well, how does this image of God in the Old Testament reconcile with the concept of Allah in Islam? This Old Testament God has children who lust after human women, marry them and have children with them. I thought that the Islamic Allah was an intangible, all-pervading being. How can such a being have sons who are capable of having sexual intercourse with humans?