Genesis 49:17

Dan shall be a serpent in the way , a viper by the path , that bites the horse’s heels so that his rider falls backward .

Dan will be a snake by the roadside, a viper along the path, that bites the horse`s heels so that its rider tumbles backward.

Dan shall be a serpent by the way, an adder in the path, that biteth the horse heels, so that his rider shall fall backward.