“right…left.” Jesus taught that at the Sheep and Goat Judgment, the sheep will be placed on his right side and the goats on his left side. Everyone in that biblical culture immediately understood from Christ’s words that the sheep were blessed and the goats were cursed. In the biblical culture, people were taught to wipe themselves with their left hand after they went to the bathroom. In contrast, they were taught to eat, give gifts, touch another person, etc., with their right hand. Thus the left hand was known as the hand of cursing and the right hand as the hand of blessing. Meals were communal, and the food was served in communal dishes. We see an example of that at the Last Supper when Jesus said that the one who dipped his piece of bread in the dish with Jesus would betray him (Matt. 26:23; Mark 14:20). For anyone to eat with their left hand would be considered completely unacceptable and they would have been immediately expelled from the meal (this custom is still practiced in some places where people eat with their hands from communal dishes, such as some parts of India). When Christ put the goats on his left, he was clearly communicating that they were cursed, which we see play out later in the chapter when they are thrown into the Lake of Fire (Matt. 25:41). In contrast, the sheep on his right hand were blessed and were allowed into Christ’s Millennial Kingdom.
Ecclesiastes 10:2 says, “A wise person’s heart inclines him toward his right hand, but a fool’s heart inclines toward his left.” In this case, the wise person's heart leads to blessings, while a fool’s heart leads to bad things, including being cursed. In John 21:6, when the apostles had fished all night but not caught anything, Jesus said to cast the net “on the right side of the boat,” and the net was full of fish, which was a wonderful blessing, both as a testimony of God’s goodness and provision, and financially to those fishermen and their families, as well.
In Proverbs 3:16, Lady Wisdom has life in her right hand, and riches and glory in her left. In this case, the left hand is not a hand of cursing, but riches and glory are certainly less valuable than life and especially everlasting life. Riches and glory fade but everlasting life is forever.