In the first century, the Roman Empire had taken away the Jews’ right to execute anyone; except in one circumstance: desecration of the temple.

Before the temple at Jerusalem was destroyed in AD 70, there was a low balustrade around the temple area called the Soreg Wall. It separated the courtyard of the Gentiles from the three inner courtyards.

The approximate translation is:

No foreigner is to go past the temple fence into the surrounding area. Whoever is caught doing so can blame himself for his ensuing death.