2 Samuel 14:6

And thy handmaid had two sons
Two are observed, that her case might suit with Amnon and Absalom:

and they two strove together in the field;
they quarrelled, and fought in the field, where there were no witnesses of what they did to each other; whereby she would suggest that Ammon was killed in the field, of which there were no witnesses, and therefore Absalom ought not to die; whereas it was in Absalom's house, at his table, and where the rest of the king's sons were present, and witnesses of it:

and [there was] none to part them;
which, had there been, might have prevented the sad disaster; this, as Abarbinel thinks, is pointed at David, who when Amnon forced Tamar, did not correct him for it, nor seek to make peace between the brethren, and hence followed what had happened:

but the one smote the other, and slew him;
as say the accusers of him that is living; for the fable supposes there was none with them; however, she suggests, as the above writer observes, that one gave the first blow, and so was the aggressor; and that he that was smitten rose up in his own defence, and in his passion slew him that smote him; which is observed to lessen the crime, and to intimate that Amnon was the aggressor, who first began the sin and quarrel, in ravishing Tamar, and so reproaching Absalom; and therefore his blood was upon his own head.