“A second portion from the produce of their land was required. The whole appointment evidently was against the covetousness, distrust, and selfishness of the human heart. It promoted friendliness, liberality, and cheerfulness, and raised a fund for the relief of the poor. They were taught that their worldly portion was most comfortably enjoyed, when shared with their brethren who were in want. If we thus serve God, and do good with what we have, it is promised that the Lord our God will bless us in all the works of our land. The blessing of God is all to our outward prosperity; and without that blessing, the work of our hands will bring nothing to pass. The blessing descends upon the working hand. Expect not that God should bless thee in thy idleness and love of ease. And it descends upon the giving hand. He who thus scatters, certainly increases; and to be free and generous in the support of religion, and any good work, is the surest and safest way of thriving.” Matthew Henry
Deuteronomy 14:22“You shall truly tithe all the increase of your grain that the field produces year by year. 23And you shall eat before the Lord your God, in the place where He chooses to make His name abide, the tithe of your grain and your new wine and your oil, of the firstborn of your herds and your flocks, that you may learn to fear the Lord your God always.24But if the journey is too long for you, so that you are not able to carry the tithe, or if the place where the Lord your God chooses to put His name is too far from you, when the Lord your God has blessed you,25then you shall exchange it for money, take the money in your hand, and go to the place which the Lord your God chooses. 26And you shall spend that money for whatever your heart desires: for oxen or sheep, for wine or similar drink, for whatever your heart desires; you shall eat there before the Lord your God, and you shall rejoice, you and your household. 27You shall not forsake the Levite who is within your gates, for he has no part nor inheritance with you. 28“At the end of every third year you shall bring out the tithe of your produce of that year and store it up within your gates. 29And the Levite, because he has no portion nor inheritance with you, and the stranger and the fatherless and the widow who are within your gates, may come and eat and be satisfied, that the Lord your God may bless you in all the work of your hand which you do.