A self-piercing blind rivet is provided for apposing biological tissue together with a device for setting the same, especially through the instrumental channel of a flexible endoscope. Without the help of further instruments, it is possible to fix, approximate and appose tissue layers, the contact force while connecting the tissue layers being adjustable. The rivets are stored in the setting device, so that they can be applied in order. The rivet and setting device enable the surgeon to combine tissue discontinuities conveniently by means of an endoscope. The surgical procedure is simplified further because the rivets can remain in the body.