Pro-tithers often retreat to the last battlefield of Abraham and Jacob and content that tithes were more than food from inside Israel.
For the following reasons I think this hermeneutic is wrong.
1. It ignores the law of the land and refuses to accept anything from outside the Bible regardless of how well it can be verified from extra-biblical sources.
2. It ignores the fact that these pre-Law tithes were not holy tithes from inside God's unique holy land of Israel.
3. It ignores the fact that these pre-Law tithes had not been miraculously "increased" by God's hand rather than by man's hand.
4. Most important, the tithe taught in the Law are, without a doubt, defined by the Law and are not defined by pre-Law tithes. Leviticus 27:34 reminds the reader "These are the commandments, which the LORD commanded Moses for the children of Israel in Mount Sinai." Numbers 18:8 calls itself an "ordinance" of the Law. Nehemiah 10:29, the context of Malachi, says "They clave to their brethren, their nobles, and entered into a curse, and into an oath, to walk in God's law, which was given by Moses the servant of God, and to observe and do all the commandments of the LORD our Lord, and his judgments and his statutes." Malachi 4:4 reads "Remember ye the law of Moses my servant, which I commanded unto him in Horeb for all Israel, with the statutes and judgments." And Matthew 23:23 is in the context of "matters of the law." None of these texts apply to the Church.
5. A court of law would not permit a definition of "tithe" from outside the boundary of the Law being discussed, that is, the Old Covenant Law of Moses given at Sinai.
For example the word "steal" in baseball mans to "steal a base" while the word "steal" in basketball and football means to "steal the ball." It is the same difference trying to define "tithe" from pre-Law when the context is Law.
6. When Jesus used the word "tithe" he used it in the context of its definition from the law.
7. Therefore the argument that tithes can includes money and materials from outside God's holy land should be thrown out on the grounds that neither the Law nor Jesus defined it as such.