New Defender's Study Bible Notes
19:30 dwelt in a cave. There have been “cave-dwellers” all through history, not primitive ape-men, but true cultured humans, forced by circumstances into such habitations. This home was quite a comedown for a family accustomed to material luxuries. The caves of the Dead Sea region have been inhabited by many people over the centuries. In fact, the famous Dead Sea Scrolls were found in such caves, left by communities of the Essene sect. Note also Job 30:3-6.
19:36 child by their father. This case of incest is not specifically condemned in Scripture, presumably because the Mosaic laws against incest had not yet been given. Lot’s daughters knew, for example, that their great uncle, Nahor, had married his niece, their own Aunt Milcah (Genesis 11:27-29), and that Abraham’s wife Sarah was his half-sister (Genesis 20:12). Nevertheless, their particular act was unnatural, to say the least, and they knew their father would not consent to it if he were sober. To their credit, they had remained virgins up to this time (Genesis 19:8), even in a licentious city like Sodom and were not motivated by physical lust, but by their concern that their family not be left without descendants. They should have merely trusted God concerning this need, however. The people descended from them, the Moabites and Ammonites, were perpetual enemies of the Israelites.