Hand quilting - how to attach bias tape?

I am attaching bias tape to my quilt to close it up - I am doing a running stitch inside the fold on the top of the bias tape and a whip stitch/blind stitch on the back side. My question is, when doing the running stitch do I sew through all of the layers? Or do I only take the needle and thread into the batting and come back out the top again so there is no seam showing on the back? Thanks!