If in truth — i.e., with serious purpose. The bramble can hardly believe in the infatuation of the trees.
Put your trust in my shadow. — The mean leaves and bristling thorns of the rhamnus could afford no shadow to speak of, and even such as they could afford would be dangerous; but the fable is full of fine and biting irony.
If not. — The bramble is not only eager to be king, but has spiteful and dangerous threats — the counterpart of those, doubtless, which had been used by Abimelech — to discourage any withdrawal of the offer.
Let fire come out of the bramble. — Some suppose that there is a reference to the ancient notions of the spontaneous ignition of the boughs of the bramble when rubbed together by the wind. The allusion is far more probably to the use of thorns for fuel: Exodus 22:6, “If fire break out, and catch in thorns, so that the stacks of corn... be consumed;” Psalms 58:9, “Or ever your pots be made hot with thorns;” Ecclesiastes 7:6, “the crackling of thorns under a pot.”