Do not be sexually intimate with one’s daughter
Even if she was born through immoral relations she is nevertheless his daughter.
This prohibition does not appear explicitly but was derived through a “lenient law applying to a strict one” and “tradition of similar words in a different context”.
The punishment is death by burning.
If done wilfully without prior warning the penalty is spiritual severance.
If done unwittingly a sin offering is required.
If she was the daughter by his wife, he would be required to bring 2 sin offerings (includes -121)