The original image (without the skull superimposed) is considered a sacred ikon by the Eastern Orthodox Church. The superimposition of the skull on this image is in no way meant as disrespect. It is in fact meant to convey the two-fold nature of Christ: being both fully God and fully man.

This image was used on posters for my Master's recital entitled, Ikonicity.

You can find a link to a page with the original image here.