Ein Aya Shabat Chapter A Paragraph 60

The Time and Place for Understanding Mitzvot and Not

The Mitzvot include both Mishpatim (understandable) and Chukim (non-understandable). Rav Kook posits that the differentiation between the two is consciously unclear, because study turns the Chukim into rational, and society sometimes interchanges what was thought as rational into a chok (e.g. homosexuality may be seen differently, but it's always wrong).