I'm wondering how a planet in retrograde might affect the interpretation of a Sabian symbol?
If your planet is retrograde then generally its action is more inwards and contemplative and has the appetite to 'go over things again just to be sure'.
The Sabian Symbols are multi-layered, having various modes of expression. They can express quite literally or they can be subtle metaphors and take time and serious thought to uncover.
A retrograde planet is likelier to support repeated enquiry, delving and checking, in order to winkle out secrets and hidden wisdom. Although this can limit the unfettered, spontaneous outer expression of an energy, it has the bonus of making possible a close alignment with the deepest wisdom that can be revealed.