Historical source of the balancing exercises?

[Nau7ik]

I think most of what Ra taught is 'cosmic' or universal in origin, rather than information sourced from human mystics, who were also interpreting universal truths from their unique perspectives.

If there's a historical precedent, it either dates back to Ra's time on Venus, the billions of years they spent in higher densities, a previous entity that Ra themselves may have learned from, or a timeless source.

Perfect response. Balance is a universal principle. It is the Key to spiritual evolution. So any true teacher of the positive polarity will recommend that which brings balance.

However, yes, these same principle can be found in the Western Mystery Tradition and the Eastern traditions.

The Tree of Life shows three pillars, the Pillar of Mercy (Positive pole) and the Pillar of Severity (Negative pole) with the Pillar of Mildness in the middle. The two side pillars are extremes whilst the middle pillar is the equilibrium between the two poles. By way of the Middle Pillar does consciousness elevate itself to higher levels. There is a direct pathway to God (Kether) through the Middle Pillar.