Here is a good lesson on parenting, based on how God disciplined Cain (Gen 4:6-7):  appealed to Cain’s conscience by asking a question,  explained to Cain the benefits of obedience,  pointed out the consequences of rebellion,  reminded Cain of the power of temptation and sin in his life, as well as the resources he already possessed to overcome them,  left it up to Cain to decide, right or wrong, and to face the consequences. Human character growth cannot happen unless the exercise of free choice is permitted. Yet, when the free choice leads to wrong deeds, the culprit is punished (Gen 4:11-12).
God is a merciful Saviour despite man’s sin, e.g. protecting Cain, appointing Seth to replace Abel. He will always accept our repentance no matter what the situation is.
This next toledot section starting in chapter 5 presents these themes: [a] the interconnectedness of all mankind and the hope of universal blessing, [b] the continuation of God’s promise of preservation through the gift of procreation, [c] the rivalry between an unrighteous lineage and a righteous lineage, [d] the progress and universality of human wickedness.
Why are genealogies included in the Bible? The Hebrews passed on their beliefs through oral tradition. For many years, writing was primitive and not easily available. Stories were told to children who passed them on to their children. Genealogies gave a skeletal outline that helped people remember the stories.
What are the general purposes of genealogies? [a] Genealogies are designed to celebrate life and accomplishment by tracing the continuation of family. [b] Genealogies point out that people are important to God as individuals, not just as races or nations. [c] Genealogies confirm the historicity of the records. The book does not contain myths.
What is the specific purpose of this genealogy in Gen 5? In Genesis, genealogies also confirm God’s promise that the coming Messiah would be born into the line of Abraham. This genealogy in Gen 5 records only the descendants from Seth because they were the chosen branch.
What are 2 types of genealogies? [a]vertical or linear genealogy: tracing one line of descent, concentrating on the chosen line, e.g. 5:1; 11:10 (but not necessarily the eldest sons); [b]horizontal or segmented genealogy: tracing through several children, e.g. 10:1; 25:12; 36:1.
5:1 the book of the generations: this is the beginning of the next division in Genesis, the 2nd time with the phrase “the generations of” (Heb. toledot) and the 3rd division of the book; only in this time (of a total of 10 times) is “the generations” preceded by “the book” (literal “written”; similar to “Book of the Wars of the Lord” in Nu 21:14; “Book of Jashar” in Jos 10:13). A possible reason is that the information was originally in another document.
All human beings are related, going back to Adam and Eve.
in the likeness of God: recapitulation of Gen 1:26-28; 2:7. It would seem that despite human fallenness, divine image and blessing were continued among the human family without suspension.
5:2 blessed them and named them Man: The blessing and naming were normally done by the father. This reminds us that God is our Father.
5:3 named him Seth (2nd generation): Seth’s naming was done by Adam, apparently contradictory to Gen 4:25; however, the name might have been proposed by Eve but formally named by Adam.
Note that Cain was not mentioned, so were all the other descendants of Adam. The others were all unimportant in salvation history.
The format used for Adam in v.3-5 is duplicated throughout the remainder of the chapter: “X was ___ years old when he fathered Y (son). X lived ___ years after the birth of Y, and he fathered sons and daughters. X’s life totalled ___ years; then he died.”
5:4 930 years: 7 of 10 patriarchs lived over 900 years. Apart from Genesis, the Bible only records 4 people living over 100 years: Job (age over 170, Job 42:16), Moses (age 120, Dt 34:7), Joshua (age 110, Jos 24:29), and Jehoiada the priest (age 130, 2Ch 24:15).
In Mosaic law, long life was the result of God’s blessing for obedience (Ex 20:12; Dt 5:16; Eph 6:2-3).
5:5 he died: final fulfilment of God’s warning of certain death in Gen 2:17.
Enosh (3rd generation): The name is a common noun in Hebrew meaning “man”, perhaps referring to man as a mortal, describing the weakness, frailty, and misery of man’s state. Regular public worship appeared after the birth of Enosh (Gen 4:26). Although the Bible did not clearly attribute this to Enosh, it was likely that Enosh had made a major contribution to such practice.
5:9 Kenan (4th generation): name possibly another form of “Cain”, though unsure; or meaning “fixed”.
5:12 Mahalalel (5th generation): name probably meaning “praise God” or “praise of God” as “-el” is a contraction of Elohim. The fact that Kenan gave his son Mahalalel, a name related to God, indicates that he still recognized God and attributed importance in his belief.
5:15 Jared (6th generation): name possibly meaning “servant” or “to go down, descend.”
5:22 Enoch (7th generation, also in Jude 1:14): name meaning “introduce” or “initiate”.
walked with God: same description for Noah (Gen 6:9); translated “well pleased to God” in Septuagint. He kept a constant harmonious and intimate relationship with God whatever he did and wherever he went. This continued for 300 years.
The expression “walk with God” is similar to the service of a loyal servant who goes before his master. The emphasis is on communion and fellowship.
For the psalmist, to “walk before God” means life and prosperity (Ps 56:13; 116:9).
Question: What is the meaning of walking with God?
Answer: (John Wesley)
[a] It is to set God always before us, and to act as those that are always under His eye.
[b] It is to live a life of communion with God, both in ordinances and providences.
[c] It is to make God’s word our rule, and His glory our end, in all our actions.
[d] It is to make it our constant care and endeavour in every thing to please God, and in nothing to offend Him.
[e] It is to comply with His will, to concur with His designs, and to be workers together with Him.
after he fathered Methuselah (8th generation): The name of Methuselah may mean “the warrior holding a spear”. But it can also mean “he dies, and the sending forth”, meaning that something would be sent after he died. The genealogy shows that Methuselah died exactly in the year that the Flood came. Jewish tradition recorded that Methuselah died “seven days before” the Flood. The Bible does not clearly indicate how Methuselah died, so it is of course possible that Methuselah was drowned in the Flood. However, it is unlikely that Noah would abandon his aged grandfather to certain death. (Noah’s father Lamech died 5 years before the Flood.)
If Methuselah’s name is related to the Flood, then Enoch named Methuselah as a prophesy to the coming Flood 969 years before it actually happened. The Bible recorded that he walked with God after Methuselah was born. It is likely that he received this prophecy from God about the Flood and this motivated him to walk with God.
Furthermore, the long life of Methuselah would have had an additional meaning. Since it was God’s plan that the Flood would come after Methuselah’s death, then his longest life span in the whole Bible would have signified God’s attribute of being merciful and long-suffering—to wait as much as possible for human beings to change their ways and to avert God’s harsh judgment.
had other sons and daughters: Walking with God does not require someone to live away from his normal life.
5:23 365 years: same number as the days in a year; probably symbolizing perfection, or a perfect time period for a perfect life.
5:24 he was not: translated “he was not found” in Septuagint; meaning disappeared.
The repetition of “Enoch walked with God” (v.22,24) was probably intentional in order to dispel any idea that the patriarch’s shorter life was a punishment for sin.
God took him: “Took” may mean that Enoch died naturally (Ps 73:24; Jonah 4:3). But his end was clearly different from all others as everyone else was described “he died.” Moreover, Heb 11:5 clearly says he did not die. Here, “took” means Enoch was “snatched” from death (Ps 49:15) and received into the presence of God. The same verb occurs for the assumption of Elijah whom the Lord “took” in the whirlwind (2Ki 2:3,10-11). Only 2 persons in all history have not experienced death when “the gates of Hades had not prevailed.” (Mt 16:18)
Enoch’s life on Earth was much shorter than all the others recorded in this chapter. Long life is generally regarded as a blessing (Ps 34:12-13; Eph 6:2) but in particular cases (such as extremely poor health), long life may not be a blessing. If God decides that our work on this Earth is complete, then death is a blessing (2Co 5:8).
The quantity (length or age) of a person’s life is of negligible value compared to the quality of his life as reflected by his relationship with God.
In Jewish literature, because of the high esteem he received, Enoch was referred as the recipient of special revelations in heaven concerning creation and eschatological events, as recorded in 3 books of Enoch which are part of the OT Pseudipigrapha. Jude 1:14-15 actually quotes from First Enoch. The books deal with Enoch’s journey through the universe in which he is granted a view of creation, judgment, the 7 heavens, and various astronomical information.
5:25 Lamech (9th generation): The contradiction between the piety of Sethite Lamech, reflected by his prayerful hope in the Lord, and the malevolence of Cainite Lamech’s virulent boasts (Gen 4:23) could not be more sharply drawn.
5:29 Noah (10th generation): the name (Heb. noah) sounds like the word for “rest”, “relief”, “comfort”, or “console” (Heb. nahem; same word in Gen 8:4); 10 generations from Adam to Noah, a perfect number. The Septuagint reads “he will give us rest.”
relief from our work and from the painful toil of our hands: Lamech named his son Noah in the hope that he would bring his family relief from “painful toil” that Adam received after the Fall. But Noah brought more relief than Lamech would imagine. [a] The word “pain” (Heb. itsavon) is the crucial word in Adam’s and Eve’s curses. It occurs only 3 times in the Bible, first for Eve, then for Adam, and now for Noah. Therefore, the implication is that he brought relief from the curse. [b] Moreover, he brought relief for the whole mankind. After the Flood, God promised never to curse the ground and never to wipe out mankind with the Flood again (Gen 8:21; 9:11). [c] Even more, Noah provided relief to God too as he provided a way (or he is the way) for God to save mankind.
5:32 500 years old: Many patriarchs were advanced in life before children were born to them. More likely, only names for the chosen line were recorded by Moses, the author of Genesis. Noah might have other children who died before he was 500 years old. Noah’s 3 named children were all born after Noah’s 500th birthday.
Shem: The name (Heb. sem) means “name”. Perhaps it was Noah’s aspirations for his son to attain a reputation. Shem’s lineage did dominate the postdiluvian history recorded in Genesis.
Ham: The name may mean “the black land” in reference to the black fluvial soil of Egypt; it may also mean “hot”. He was the youngest son and the ancester of many of Israel’s traditional enemies.
Japheth: The name may mean “expand” or “extend”. The word may be related to the Egyptian word for the island Crete.
Question: Did the list in Gen 5 (or Gen 11) record the eldest sons in each generation?
Answer: Many theologians believe that the list from Adam to Noah is all for the eldest sons because the Hebrew tradition gives special honour to the eldest son. But there is no clear evidence from the Bible. The list actually follows only the chosen line from Adam to Noah, not necessarily following the eldest sons because:
 In the case of Adam, Seth was born when Adam was 130 years old and he was clearly not Adam’s eldest son; Cain was (Gen 4:1). Moreover, when Cain was exiled, there were already other people in the world. They must be the children and descendants of Adam and Eve born before Seth. Similaly, Arpachshad (Gen 11:12) was apparently the third son of Shem (Gen 10:22).
 The Bible did not say that the “other sons and daughters” were born after the listed son. For example, Gen 5:7: “Seth lived after he fathered Enosh 807 years and had other sons and daughters.” The two clauses are not linked and can be independent. Some of Seth’s children could have been born before Enosh.
 Notice the large variations in their age when the listed son was born: 130 (Adam), 105 (Seth), 90 (Enosh), 70 (Kenan), 65 (Mahalalel), 162 (Jared), 65 (Enoch), 187 (Methuselah), 182 (Lamech), 500 (Noah). For some of them, they must have some other children before the one listed in Gen 5. In Noah’s case, he likely had other children before Shem and they might have died before Noah began the construction of the ark when only 3 sons are mentioned.