"Honour the LORD with thy substance, and with the firstfruits of all thine increase." (Proverbs 3:9)
There are seven New Testament references to "firstfruits," all of which are metaphorical applications of the Old Testament commandment to offer the firstfruits of one’s increase to the Lord. We now have to give our own firstfruits to the government in the form of "withheld" amounts from our wages. It is still good, nonetheless, to honor the Lord with the "firstfruits" equivalent of our increase, regardless of the government.
The New Testament references are all beautiful spiritual applications of this concept. At His resurrection, Christ Himself has "become the firstfruits of them that slept" (1 Corinthians 15:20). When we receive Christ, we receive our eternal salvation first of all in terms of "the firstfruits of the Spirit" (Romans 8:23). Furthermore, we ourselves are, to Him, a sort of firstfruits pledge of future growth. "Of his own will begat he us with the word of truth, that we should be a kind of firstfruits of his creatures" (James 1:18).
This thought is also applied to the first converts of a new mission field. Paul speaks of "the firstfruits of Asia" (the western part of Asia Minor) and "the firstfruits of Achaia" (southern Greece) in Romans 16:5 and 1 Corinthians 16:15, respectively. He also speaks of believing Jews as having preceded Gentiles into the kingdom as a holy firstfruit (Romans 11:16) to the Lord.
The last of the New Testament references to firstfruits relates to the 144,000 Israelite witnesses in the coming great tribulation. "These were redeemed from among men, being the firstfruits unto God and to the Lamb" (Revelation 14:4). Beautiful and pointed though these metaphors may be, however, they in no wise lessen our responsibility to honor God with our own firstfruits. HMM