In a post below I mentioned returning to read Karl Rahner after some years of relative neglect. In a typically dense essay, "Christianity's Absolute Claim," (Theological Investigations, volume 21) from relatively late in his life, Rahner ends on a very personal note:

In the challenge of faith which I, too, think that I have experienced, one thing has always remained clear to me, has sustained me as I have held to it. It is the conviction that what has been inherited and received must not simply be consumed by the emptiness of everyday existence, of spiritual obtuseness, of dark and gloomy skepticism, but at most by what is more powerful and calls to greater freedom and more irresistible light. The faith I inherited was certainly always the faith that was challenged and could be challenged as well. But this faith was always experienced as that person who asked me: "Will you too go away?" and to whom one could only say always: "Lord, to whom shall I go?" It was experienced as faith that was powerful and good, which I could have given up only if the opposite had been shown. Therefore, until the opposite has been proved. And now: no one has proved the opposite to me, not even the experience of my own life.

In a comment on the original post Jean Raber refers to a painting, "The Crucifixion of Saint Peter," by Luca Giordano. Rahner's words might serve to exegete the painting.NOTE:Thanks to Mollie's technical know-how, if you click on the image, and then click again, you can see an enlarged version.