Hazrat Mak’hool states that when a person pays zakat in a certain month, and then in the same month he acquires some more wealth and spends it, then there is no zakat on the wealth he has spent. However, if in the month he paid zakat he acquired some wealth which remained with him for the entire month, then zakat must be paid on it. And if in the month he did not pay zakat, he acquired some wealth, then as soon as he benefits from it, zakat must be paid on it (it is not a condition for a year to pass over it).