English: “So that you will not bring blood upon your house” — this is a negative commandment.
On the daf / in context: The verse contains both a positive commandment (to build the parapet) and a negative commandment (not to leave a dangerous situation).
Type of Learning
Derash identifying the negative commandment component.
What Is Learned
Failing to build a required parapet violates a negative commandment against causing bloodshed in one’s house.