Genesis 4:19

“And Lamech took unto him two wives, etc.] He was the first we read of that introduced polygamy, contrary to the first institution of marriage, whereby only one man and one woman were to be joined together, and become one flesh, (<010224>Genesis 2:24). This evil practice, though it began in the race of wicked Cain, was in later ages followed by some among the people of God, which was connived at because of the hardness of their hearts; otherwise it was not so from the beginning. This was the first instance of it known; Jarchi says it was the way of the generation before the flood to have one wife for procreation of children, and the other for carnal pleasure; the latter drank a cup of…”

“Lamech took unto him two wives--This is the first transgression of the law of marriage on record, and the practice of polygamy, like all other breaches of God's institutions, has been a fruitful source of corruption and misery.”

“- XIX. The Line of Cain 17. חניך chenôk, Chanok, “initiation, instruction.” 18. עירד ‛ı̂yrād, ‘Irad, “fleet as the wild ass, citizen.” מחוּיאל mechûya'el, Mechujael, “smitten of ‘El, or life of ‘El.” מתוּשׁאל metûshā'ēl, Methushael, “man of ‘El, or man asked.” למך lāmek, Lemek, “man of prayer, youth.” 19. עדה 'ādâh, ‘Adah, “beauty.” צלה tsı̂lâh, Tsillah, “shade or tinkling.” 20. יבל yābāl, Jabal, “stream, leader of cattle, produce, the walker or wanderer.” אהל 'ohel plural: אהלים 'ohālı̂ym for אהלים 'ăhālı̂ym “tent, awning, covering” of goats’ hair over the poles or timbers which constituted the original booth,” סכה sŭkâh. 21. יוּבל yûbāl, Jubal, “player on an instrument?”…”

“And Lamech took two wives - It was one of the degenerate race of Cain who first transgressed that original law of marriage, that two only should be one flesh. Jabal was a famous shepherd; he delighted much in keeping cattle, and was so happy in devising methods of doing it to the best advantage, and instructing others in them, that the shepherds of those times, nay, the shepherds of after - times, called him Father; or perhaps his children after him, being brought up to the same employment: the family was a family of shepherds. Jubal was a famous musician, and particularly an organist, and the first that gave rules for that noble art or science of music. When Jabal had set them in a way to…”

“4:19 Marrying two women was contrary to God’s ideal pattern for marriage (2:24) and might be another manifestation of the arrogance and rebellion of Cain’s descendants.”

“two wives: Gen 2:18, Gen 2:24; Mat 19:4-6, Mat 19:8 Genesis 4:20”