A device and method are provided for clips or staples as an effective substitute for suture material when joining body tissue or covering body tissue with a mesh, such as is particularly used in fracture operations. The device for applying a medical lockable clip (1) in a tissue area, includes a) an automatic advancing mechanism oriented in the direction of the tissue area from a starting position and having a guide in the advancing direction for the clip, wherein the clip has two gripper teeth oriented in the advancing direction, b) a stop for the advancing mechanism, and c) a locking element displaceable with the advancing mechanism and having a locking mechanism on the clip side for locking the clip, wherein d) the locking element is displaceable together with and parallel to the advancing mechanism, and e) the stop does not limit the motion of the locking element.