Joseph F. Smith taught that if one got church assistance one had to pay tithing on that too.
Ordinarily it is expected that members of the Church who are admitted into the house of the Lord are men and women who pay their tithing and their offerings, and who are faithful in all other duties devolving upon members of the Church. It is not expected that the names of children eight years old and upwards, who are generally living with their parents, will have to be upon the tithing records in order to permit them to enjoy this privilege; for they will accompany their parents, and will be entitled to whatever recommendation is necessary to admit them there. But men and women of long standing in the Church, who have neglected their tithes and their offerings, and people who have established a character for drunkenness, for profanity, for infidelity, or for unfaithfulness to their duty in the Church of God, should not have the privilege of a recommendation to the dedication of the house of God. That is as I understand it. It is, I believe, as it was decided by the Presidency and Apostles not long ago. I think that this is as it should be. Every right-thinking person, member of the Church or otherwise, cannot look upon it consistently in any other light. If we expect privileges and blessings which pertain to the Holy Priesthood and to the Gospel of Jesus Christ, we must be subject to the laws and to the conditions upon which those blessings and privileges are promised. To grant to any man or woman rights and privileges which pertain to the Gospel, for which he or she is unworthy, would be a cause of just complaint and objection on the part of those who are faithful. Furthermore, it would be a laxity that would not be consistent or characteristic of the government of God among men. Therefore, if we desire a blessing, let us observe the conditions upon which the blessing is promised, and let us live worthy of that blessing, so that we may be in a position to receive it when it is offered unto us. The Prophet Joseph declared that "there is a law, irrevocably decreed in heaven before the foundations of this world, upon which all blessings are predicated; and when we obtain any blessing from God, it is by obedience to that law upon which it is predicated." If we desire to obtain the blessings that the Lord has promised on condition of keeping the law of tithing, we must keep that law, no matter how poor or how dependent we may be. The law is as binding upon the widow and the poor, as it is upon the rich. Why? Because it is a general principle applicable to the increase of all, the rich and poor, alike, and a principle of blessing. "Prove me now herewith, saith the Lord of hosts, if I will not open you the windows of heaven, and pour you out a blessing, that there shall not be room enough to receive it." That is the promise. Now, [p.240] if the poor pay their tithing out of the little they receive, however small their offering to the Lord may be, it will prove to Him that they are honoring a law that He has instituted by which they are to know whether they are worthy to be numbered with the Saints, or to stand in their lot and place in Zion, or not; for if we do not honor this law, this land, saith the Lord, will not be a land of Zion unto us. Furthermore, if I were dependent upon the Church, drawing my support from the Church, and had not means nor strength wherewith to provide otherwise for myself, one-tenth of it I would give back to God. I would thereby honor a law that He has instituted that I might be worthy to stand in Zion with His Saints, and that the land might be sanctified unto me as a land of Zion. The same with every other law that God has revealed to the children of men. But some may think this is carrying matters to an extreme. I do not think so. I see no extreme about it. I see merely a principle, one that is applicable to all of us, and which we are in duty bound to honor, as much as we are to honor the principle of baptism for the remission of sins, or any other ordinance of the house of God, whether we are poor or otherwise, in order to make our standing and professions before the Lord consistent. I am in duty bound, according to the covenants which I have made with God, to be honest, chaste, virtuous, and to keep myself pure and unspotted from the world; but I am under no greater obligation to observe one principle than I am another. I should keep every commandment and every law, in every particular, and then I would be worthy before the Lord. He then would, without doubt, accept of my labors and offerings, and sanctify the land unto me. (Joseph F. Smith, Brian Stuy, Collected Discourses Vol.3, p. 240)
While this matter of non-tithe-payers was being talked over, I heard of a Bishop who refused to receive tithing from a person because that person was poor. I wondered what Bishop it was. What Bishop is there in the Church who would deny a woman, even though she was fed and clothed out of the tithings of the people, the privilege of having her name recorded in the books? I will read a few words out of the same revelation that Brother Clawson has read to us this morning:
"It is contrary to the will and commandment of God, that those who receive not their inheritance by consecration, agreeably to this law, which He has given, that He may tithe His people, to prepare them against the day of vengeance and burning, should have their names enrolled with the people of God;
"Neither is their genealogy to be kept, or to be had where it may be found on any of the records or history of the Church;
"Their names shall not be found, neither the names of the fathers, nor the names of the children written in the book of the law of God, saith the Lord of hosts."
Will you then deny the widow, because she has only a mite to bestow? Because the tenth which she proposes to give in obedience to the commandment of God is but a penny, are you going to deprive her of the privilege of having her name enrolled on the book of the law of the Lord, and of having her genealogy acknowledged and recorded in the archives of the Church? And because her name is not found there, are you going to deny her the privileges of the House of God and of the ordinances of the Gospel? I think it is time the Bishops understood this principle. The Bishop should encourage every man, woman and child that earns and receives in return for his labor, to honor the Lord and to prove his obedience to the law of God by giving the one-tenth of that which he or she receives, as the Lord requires, so that they may have their names enrolled on the book of the law of the Lord, that their genealogies may be had in the archives of the Church, and that they may be entitled to the privileges and blessings of the house of God. Joseph F. Smith, Conference Report, April 1900, p. 47-48
Getting welfare is an increase, so you are required to pay tithing on it.