Explanation of the author's statement: "It becomes obligatory with five conditions: freedom, Islam, ownership of the nisab, its stability, and the passage of the hawl."

The Shaykh : However, it is not obligatory except with conditions. And among the wisdom of Allah (Mighty and Majestic) and His perfection in His obligations and legislations is that He established specific conditions for it, meaning specific attributes, without which it is not obligatory, so that the legislations are regulated and not chaotic. If there were no conditions, everyone would estimate that this is obligatory and that is not obligatory. So when the obligations are perfected with conditions and defined, there is no chaos; people are on knowledge and insight: when the conditions are present in something, it is established, and when they are absent, it is absent. Then, there are obstacles that prevent the obligation of zakah even when the conditions are present, because all things are not completed except with their conditions and the absence of their obstacles. The explanation of the obstacles, and what is agreed upon and what is disputed regarding them, will come, if Allah wills.
He says: "It becomes obligatory with five conditions: freedom, Islam, ownership of the nisab, its stability, and the passage of the hawl". These are the five conditions. The first is freedom, and its opposite is slavery. So zakah is not obligatory on a slave, meaning a male slave, because he does not own; the wealth in his hand belongs to his master. The evidence for that is the saying of the Prophet (peace and blessings be upon him): He said, "His wealth," meaning what is in his hand, belongs to the one who sold him, not to him. So he is in the position of the poor person who has no wealth, and zakah is not obligatory on the poor person by consensus.
The second is Islam, and its opposite is disbelief. So it is not obligatory on a disbeliever, whether he is an apostate or an original disbeliever, because zakah is a purification. And the disbeliever is impure; if he were purified with the water of the sea and the earth filled with gold, he would not be purified until he repents from his disbelief. And if we say that zakah is not obligatory on the disbeliever, that does not mean that he is not held accountable for it; rather, he is held accountable on the Day of Resurrection, but it is not obligatory on him in the sense that we do not compel him to it until he becomes a Muslim. The evidence for that is the saying of the Prophet (peace and blessings be upon him) when he sent Mu'adh to Yemen: After mentioning tawhid and prayer, he said: And from the Qur'an: If it is not accepted from them, then there is no benefit in compelling them to it, but they are held accountable for it on the Day of Resurrection and punished for it. The evidence for that is His saying (Mighty and Majestic) about the criminals: This is leaving off prayer. This is leaving off zakah. If they had not been punished for leaving off prayer and leaving off feeding the poor, they would not have mentioned that as a reason for their entering the Fire.
The third is: "Ownership of the nisab". What is the nisab? The nisab is the amount that the Lawgiver established the obligation of zakah upon reaching. It varies, so one must own a nisab. If one does not own anything, like the poor person, then nothing is required of him. If one owns less than the nisab, then nothing is required of him. If it is estimated that a person does not have a full nisab at the completion of the hawl, then there is no zakah on him, because he has not owned the nisab.
The fourth is: "Its stability". The stability of ownership means that the owner of the thing owns it with stable ownership, and in its being stable, it is not exposed to destruction. If it is exposed to destruction and inability to retain it, then there is no zakah in it. They gave as an example for that the rent of a house before the completion of the period, for it is not stable, because it is possible that the house collapses and the rent contract is annulled. If the house collapses, the rent contract is annulled. They also gave as an example for that the debt of manumission, meaning if the master sells himself to his slave for dirhams and the slave retains it for a year, then there is no zakah in it. Why? Because the slave owns the ability to declare his own inability and say, "I am not able to pay." And if he is not able to pay, then the money with which he bought his freedom is dropped from him, so the debt at that time is not stable. It must be stable such that its owner is safe from its destruction. Yes.
The fifth is the passage of the hawl, meaning its completion, meaning the completion of the hawl. Because the Prophet (peace and blessings be upon him) said: Narrated by Ibn Majah. And because if we did not estimate a time, would we say that you purify it every day, or every month, or every week, or every ten years? So an estimation is necessary. The hawl is a measure by which profit is generally continuous, and fruits are in it, and increase is in livestock generally. For this reason, it was estimated by the hawl.