Adam Clarke's Bible Commentary Verse 1. The book of the generations] rps sepher, in Hebrew, which we generally translate book, signifies a register, an account, any kind of writing, even a letter, such as the bill of divorce. Here It means the account or register of the generations of Adam or his descendants to the five hundredth year of the life of Noah.
In the likeness of God made he him] This account is again introduced to keep man in remembrance of the heights of glory whence he bad fallen; and to prove to him that the miseries and death consequent on his present state were produced by his transgression, and did not flow from his original state. For, as he was created in the image of God, he was created free from natural and moral evil. As the deaths of the patriarchs are now to be mentioned, it was necessary to introduce them by this observation, in order to justify the ways of God to man.
Matthew Henry Commentary
Verses 1-5 - Adam was made in the image of God; but when fallen he begat a son in his own image, sinful and defiled, frail, wretched, and mortal, lik himself. Not only a man like himself, consisting of body and soul, but a sinner like himself. This was the reverse of that Divine likeness in which Adam was made; having lost it, he could not convey it to his seed. Adam lived, in all, 930 years; and then died, according to the sentence passed upon him, "To dust thou shalt return." Though he di not die in the day he ate forbidden fruit, yet in that very day he became mortal. Then he began to die; his whole life after was but reprieve, a forfeited, condemned life; it was a wasting, dying life Man's life is but dying by degrees.
Original Hebrew זה2088 ספר5612 תולדת8435 אדם121 ביום3117 ברא1254 אלהים430 אדם120 בדמות1823 אלהים430 עשׂה6213 אתו׃853