Zen Buddhist koan to ward off the student from the fallacy of worship.
It likens the Buddha to a finger pointing at the Moon. The student can either concentrate on the finger (i.e., worship the Buddha), or look at the Moon (i.e., study what the Buddha taught).
Naturally, you can substitute any religious, spiritual, philosophical, political (etc) leader, founder, teacher (etc) for the Buddha.
For example, I have heard a Zen master describe the difference between Christians and Buddhists using this koan, when he said, "Both Christ and the Buddha were a finger pointing at the Moon. But Christians look at the finger, while Buddhists look at the Moon."