This is a strange argument from silence. Just because Genesis did not record him regularly tithing, its plain silly to say Abraham did not do it.
Imagine if the Bible included Jacob, or Issac or Abraham tithing, it will sound like this
Genesis 18:33 When the Lord had finished speaking with Abraham, he left, and Abraham returned home, and Abraham tithe to the Lord
Genesis 26:12 Isaac planted crops in that land and the same year reaped a hundredfold, because the Lord blessed him, and Issac tithe to the Lord.
Can you see how silly it is for the Bible to record down every time these people tithe, in order to convince us Christians 2000 years later that tithing was before the Law?
My reply:
1st:
Gen chapter 18 isn't about tithing. Gen 18:33
KJV 33 When the Lord had finished speaking with Abraham, he left, and Abraham returned home.
AMP 33 33 As soon as He had finished speaking with Abraham the Lord departed, and Abraham returned to his own place.
ESV 33 And the Lord went his way, when he had finished speaking to Abraham, and Abraham returned to his place.
Douay-Rheims 1899 American Edition 33 And the Lord departed, after he had left speaking to Abraham: and Abraham returned to his place.
NIV 33 When the Lord had finished speaking with Abraham, he left, and Abraham returned home.
What I find silly & frankly shameful, is the FALSE narrative presented in your post.
Gen chapter 26 context isn't about tithing either.
2ndly: Some facts on tithing pre-law:
Jacob did tithe, however, NOT under a must give system. His free will giving, came with his own conditions. IF YOU/GOD DO, I WILL!
After wrestling with the Lord Gen 32:28. The Lord changes Jacobs name to Israel. Jacob's 12 sons become the 12 Tribes of Israel. Each son receives a portion of Land except Levi. Leiv's Tribe is chosen to be the priests.
Before the Mosaic Law is implemented Abraham's grandson Jacob makes a FREEWILL vow to God: "IF GOD"
Gen. 28:20 And Jacob vowed a vow, saying, If God will be with me, and (IF GOD) will keep me in this way that I go, and ""IF GOD"" will give me bread to eat, and raiment to put on,
21 So that I come again to my father's house in peace; then shall the LORD be my God:
22 And this stone, which I have set for a pillar, shall be God's house: and of all that thou shalt give me I will surely give the tenth unto thee.
(NOTE: Jacob's proposition is "IF GOD" meet's Jacob's requirements. He will give God back 10%.)
Point: this was a freewill 10% offering. And only made on the increase of things already in Jacobs possession. NEVER on something future, like an unearned paycheck.
No Mosaic Law, no Levitical Priests, no local Churches. So, how or to whom did Jacob tithe? Two different way's:
Deut. 12:6 & 7 & 14:29
6) Bring your freewill offering, (7) have a communion meal with God/Christ. (14) Now freely share/give to the, poor, the stranger, the fatherless & the widow. And God will bless you in all the work of thine hand.
3rdly:
The purpose of the tithe, under the Mosaic law. Was because, unlike all the other tribes. The Levites did not reveice or own any property. Therefore had no means of income. So God provided for the Levite tribe, the priestly’ tribe. With the tithes (Plural) of the other tribes. So the tithe is not biblical, unless it is given to the Levites.
4th Landowners only! Paid tithe on product & animal INCREASES!
A fisherman paid nothing on his catch, tradesmen, cobblers, who made the shoes for the servants of the field, did not tithe. Carpenters, potters, the women, who made the soliders garments, the servants who worked in the fields for wages, did not tithe.
The tithe was exclusively a tax on the produce on the land of Israel land & animals. So if you didn't live within the Promised land (Israel), then you were not required to pay tithe. Numbers 18:21 clearly states; “all the tithes in Israel,” tithes were only paid on people’s increase (Deuteronomy 14:22), on their agricultural products (Leviticus 27:30), within the land of Israel & the owners herd & flocks Lev 27:32.
Land owners paid three tithes of a tenth each, not one. The Levitical tithe (Numbers 18:19-20), the festival tithe (Deuteronomy 14:22-17), and the poor tithe, every 3rd year (Deuteronomy 14:28-29). Paid to the tribe of Levi within one of 48 designated cities within Israel (Numbers 35:7).
Every 7th (Sabbath) year (Exodus 23:10-11), and 50th (Jubilee) year (Leviticus 25:10-11), the entire nation of tithers, within the nation of Israel were completely excluded from paying tithes for those ENTIRE YEARS.
Any Churches you know preach this?
Finally: New testament giving:
1 Cor 16:2 Upon the first day of the week let every one of you lay by him in store, as God hath prospered him, that there be no gatherings when I come.
(NOTE: Bring WEEKLY your best freewill gift)
2 Corinthians 9:6 But this I say, He which soweth sparingly shall reap also sparingly; and he which soweth bountifully shall reap also bountifully.
(NOTE: Give a little, receive a little, give alot, receive alot)
7 Every man according as he purposeth in his heart, so let him give; not grudgingly, ""or of necessity"": for God loveth a cheerful giver.
(NOTE: A tithe was given out of the laws necessity. A worthless gift from todays believer. A freewill gift from the heart is loved and rewarded by our Lord. Even a drink of water given in His name Mk 9:41)
When it comes to giving. New covenant Christians are taught to give generously, sacrificial & expectant of a blessing in return. And most certainly be CHEERFULL FREEWILL GIVER'S!
We should all prayerfully examine our giving patterns. Pray earnestly that the Holy Spirit would challenge us. To see whether they are in line with God's New Testament plan of being Generous, Sacrificial, Cheerful Giver's!
2
