What is God’s punishment for thieves? Ex in the OT are there any instances of punishment? Is there a theme of punishment for this?
They must repay some multiple of what has been stolen. If they cannot pay, the Torah permits them to be sold into indentured servitude unless their family pays the debt for them.
Israel, thinking that his sons might be accused of theft over the money they found in their sacks, told them to return double the money. (See Genesis 43:12)
If a man steals an ox or a sheep, and kills it or sells it, he shall pay five oxen for an ox, and four sheep for a sheep. He shall make restitution; if he has nothing, then he shall be sold for his theft. If the stolen beast is found alive in his possession, whether it is an ox or an ass or a sheep, he shall pay double. (Exodus 22:1, 3b-4 RSVCE)
Note: Ordinarily, Jews had to free their Jewish slaves after six years. (See Exodus 21:2)
When the prophet Nathan proposed to king David the case of a rich man who took and killed his poor neighbor’s lamb, David passed a judgment of fourfold restoration. (See 2 Samuel 12:6)
After coming to faith in Jesus, Zacchaeus pledged to repay fourfold anyone he had defrauded. (See Luke 19:8)
Also, at any time he could redeem himself or be redeemed by his family if he/they legitimately come into sufficient resources to do so (a bondsman could, for example, inherit land from his father and lease it out to acquire the money to pay his debt).
There are no themes of punishment for sin.
And then he figured out what the story was about…