The answer is: It is not obligatory upon him; rather, it is obligatory upon them. This is the established position of the school, unless it is stipulated as part of their wages that he must provide for their maintenance, in which case it is obligatory upon him.
As for Zakah al-Fitr on behalf of a slave, it is obligatory upon his master, because Muslim narrated in his Sahih from Abu Hurayrah that the Messenger of Allah (peace and blessings be upon him) said: “No charity is due on a slave except the charity of Fitr.” (1) Thus, this hadith qualifies Ibn Umar’s hadith with respect to Zakah al-Fitr on behalf of a slave. Moreover, the slave belongs to his master and owns nothing, so the master is required to purify him, since the slave cannot possess wealth.
Some scholars said that it is obligatory upon the slave himself, and that the master must free the slave’s time at the end of Ramadan so that he may earn what he can use to pay the charity of Fitr. This is weak for the following reasons:
First: the hadith authentically establishes an exception for slaves.
Second: one of the established legal principles is that whatever an obligation cannot be fulfilled without is not itself obligatory. Thus, one is not told: “Engage in trade so that Zakah becomes obligatory upon you.”
“Even if it is only for the month of Ramadan. If he can afford only some of them, he begins with himself, then his wife, then his slaves, then his mother, then his father . . .”
His statement, “Even if it is only for the month of Ramadan,” means that if a person supports a man only during the month of Ramadan, Zakah al-Fitr on his behalf is obligatory upon him.
For example, if a guest stays with you from the first day of Ramadan until the last day, you must pay Zakah al-Fitr on his behalf, because you are supporting him during that month. This view is based on the preceding position that Zakah al-Fitr is obligatory upon the one who supports another person. It has already been mentioned that the correct view is that it is not