652. Amira l’Akum
90:14 Anything that a Jew may not do on Shabbos, he likewise may not instruct a non-Jew to do because telling a non-Jew (amira l’akum) is included in the concept of cessation of labor (shvus). Even to hint to a non-Jew to perform labor is prohibited, as is instructing him before Shabbos to do some act of labor on Shabbos. Similarly, one may not direct a non-Jew on Shabbos to perform an act of labor after Shabbos. That last restriction is not because of shvus since the work is being performed at a permitted time. Rather, it is prohibited because of pursuing one’s own affairs on Shabbos. Therefore, one may instruct a non-Jew to perform a labor after Shabbos for the sake of a mitzvah. (One only may not direct a non-Jew to perform an act that is actually prohibited; one may have him do something that is only not done as a stringency – Mishnah Brurah 307:8. One may hint to a non-Jew on Shabbos to perform a labor after Shabbos – Rema 307:22.)
90:15 If the non-Jew comes on his own to perform some forbidden labor for a Jew, the Jew must object. For example, if a non-Jew wants to remove the burnt material from a Jew’s candles in order to help them to burn better, the Jew must dissuade him. (If there is usable light even without the non-Jew’s actions, then the Jew may allow the non-Jew to improve it; he may even hint to the non-Jew to do so - MB 307:76.)