I wanted to include some modern revelation on the topic of tithes and offerings:
Pay Tithes and Offerings - Successful family finances begin with the payment of an honest tithe and the giving of a generous fast offering. The Lord has promised to open the windows of heaven and pour out great blessings upon those who pay tithes and offerings faithfully (Malachi 3:10 and Isaiah 58: 6–12).
Tithing - If our tithing is the first obligation met, our commitment to this important gospel principle will be strengthened and the likelihood of financial mismanagement will be reduced.
Fast Offerings - On fast day, we go without food and drink for two consecutive meals, if physically able, and then give to the bishop a fast offering at least equal to the value of the food not eaten. If possible, we should be very generous and give more. The bishop uses the fast offerings to care for the poor and needy. (All Is Safely Gathered In: Family Finances)
"How grateful I am for the law of tithing. It is the Lord’s law of finance. . . It comes of His wisdom. To every man and woman, to every boy and girl, to every child in this Church who pays an honest tithing, be it large or small, I express gratitude for the faith that is in your hearts. I remind you, and those who do not pay tithing but who should, that the Lord has promised marvelous blessings (see Mal. 3:10–12)." (President Gordon B. Hinckley, Ensign, January 2002)
"Some of you have money problems. I know that. There is never enough money in your homes. I know that. You are struggling to get along. What is the cure? The only thing I know of is payment of tithing. Now, that doesn’t mean that you will have a Cadillac and a mansion. But it was God who made the promise that He would open the windows of heaven and pour down blessings upon those who walked honestly with Him in the payment of their tithes and offerings, and He has the capacity to keep His promise. It is my testimony that He does keep that promise” (President Gordon B. Hinckley, Oahu, Hawaii, regional conference, 18 Feb. 1996).
Glorious is the promise of the Lord concerning those who pay their tithes. He says in modern revelation that they “shall not be burned” (see D&C 64:23). His great promise is found in the words of Malachi. Said He: “Will a man rob God? Yet ye have robbed me. But ye say, Wherein have we robbed thee? In tithes and offerings. … “Bring ye all the tithes into the storehouse, that there may be meat in mine house, and 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” (Malachi 3:8, 10). And then He goes on to say something very interesting. Listen to this: “And I will rebuke the devourer for your sakes, and he shall not destroy the fruits of your ground; neither shall your vine cast her fruit before the time in the field, saith the Lord of hosts. “And all nations shall call you blessed: for ye shall be a delightsome land” (Malachi 3:11–12).
While tithing is paid with money, more importantly it is paid with faith. I have never met an individual who paid an honest tithe who complained about it. Rather, he put his trust in the Lord, and the Lord never failed him. . . With the payment of tithing have come innumerable blessings as the Lord has promised. I was married during the Depression, when money was scarce, but we paid our tithing, and somehow we never went hungry or lacked anything we needed. (President Gordon B. Hinckley, General Conference, April 2007)