Is the one who pays zakah incompletely an apostate?

Question:
May Allah reward you. He asks: Is the one who pays zakah incompletely subject to the ruling of an apostate?

Answer:
The one who pays zakah incompletely has a debt remaining in his liability until he pays it out; his liability is not cleared except by paying it out, because it is a right of Allah (Glorified and Exalted is He), and then it is a right of the poor and the needy. It is obligatory for him to pay the zakah in full. However, he does not become an apostate unless he denies the obligation of zakah. If he denies the obligation of zakah, then he is an apostate. But if he withholds it, or withholds part of it, out of stinginess, then he is committing a forbidden act and a great major sin. It is obligatory for the one in authority to compel him to pay the zakah. If he refuses, then it is taken from him by force and distributed to those who are entitled to it.