Genesis 5

The Sin of Adam and Eve in Genesis 3 brought the downfall of Man with death accompanying it. They died spiritually immediately and physically later. 

Seth was born when Adam was one hundred and thirty years old. He then lived eight hundred more years dying at nine hundred and thirty years (V 1-5).

Seth would bear Enosh. Generation after generation would follow (V 6- 18).  Then Enoch would be born. He walked with God so closely that at three hundred and sixty-five years old, he was taken up by God (he did not die) (V 19-24).

More generations followed until Noah was born (V 25-31).

At five hundred years old, Noah was the father of three sons: Shem, Ham, and Japheth (V 32).

Thus was the line of Seth.