Lots of information on Hand Symbolism on this page, from various cultures and belief systems.
“The ancients attached special occult significance to every part of the human body. The symbolism of the human hand alone may fill several volumes. Symbols may signify abstract or concrete concepts, imaginative or real events, natural or “supernatural” phenomena, spiritual or material principles. In what we have found, the ancient sages and philosophers made used of the hands to portray and symbolize many things of worth to the evolving soul. They taught many things using the hands as similitude, allegories, analogies, and examples.
The left and right hands were often represented for the many polarities that we find and experience in life. For instance, hot/cold, high/low, darkness/light, etc. ”