Commentary for Avodah Zarah 128:13

Nahman b. Yitzchak says that the ger toshav is considered a non-Jew with regard to the issue of the eruv. An eruv is a meal shared by all members of a courtyard and allows them to carry from the house into the courtyard. But in order for this to work all members of the courtyard must participate in the eruv. A Jew who forgot to participate in the eruv may symbolically transfer or renounce his ownership, but not an apostate Jew, who does not keep Shabbat. However, if a non-Jew lives there in the courtyard, the Jews must formally rent his place. Thus the ger toshav is considered like a non-Jew with regard to the eruv. He does not “live” with the Jews. However, he may not annul idols because he does not worship them. His “religion” is like that of the Jews.