2 Samuel 13:12

And she answered him, nay, my brother,.... Which carried in it a reason sufficient for her denial, that he was her brother, and she his sister, and therefore should not offer such an indignity to her:…

Tamar’s words are a verbal quotation from Gen 34:7. The natural inference is that Tamar knew the passage in Genesis, and wished to profit by the warning that it contained. (Compare also 2Sa 13:13.)

Nay, my brother - There is something exceedingly tender and persuasive in this speech of Tamar; but Amnon was a mere brute, and it was all lost on him.

We have here a particular account of the abominable wickedness of Amnon in ravishing his sister, a subject not fit to be enlarged upon nor indeed to be mentioned without blushing, that ever any man…

no such thing ought to be done in Israel Israel was a holy nation, sanctified by the peculiar presence of Jehovah among them; and therefore all acts of unchastity were an offence against the true…