The "Law of Rhythm" is a concept that suggests that all things in the universe follow a natural, cyclical rhythm or pattern. It is often associated with the Seven Hermetic Principles from the Kybalion, a book that explores the teachings of Hermeticism.
According to this principle, everything in existence has a rhythm, including the flow of time, emotions, and even physical phenomena. The Law of Rhythm posits that things move in cycles, oscillating between two poles, such as day and night, life and death, expansion and contraction, or growth and decay.
(re-worded with artificial intelligence, I'm currently at the start of my spiritual journey, i believe this post to be true at the time of conception, and will edit accordingly as i progress on my journey).