Where does Scripture make the conference the Levites?
The Levites were named by God directly and judged by God directly — Nadab and Abihu by fire, Eli's house by prophecy fulfilled. A conference is a voted human administrative body. Before Numbers 18 or Malachi 3 can be applied to a modern denomination, it must first be established from Scripture that the conference is the biblical equivalent of the Levites — and that equivalence is always assumed, never proven.
The demand is fair, and the proof is not assumed — it is written, by an inspired hand. The equivalence claimed is functional, not genealogical: no one argues that conference workers descend from Levi, but that the tithe follows the ministry of God's appointed work in every era — and the bridge across the eras is built by Paul himself: “Do ye not know that they which minister about holy things live of the things of the temple?… Even so hath the Lord ordained that they which preach the gospel should live of the gospel” (1 Corinthians 9:13–14). “Even so” is the transfer of the Levitical support pattern to the gospel ministry, made by apostolic authority. The successor to the sons of Levi is not a corporation; it is the gospel ministry — and the treasury question is simply how a worldwide gospel ministry is lawfully sustained.
Then how does God appoint that ministry, absent fire from heaven? The way He appointed it in the apostolic church: through His organized body. Gifts were laid at the apostles' feet; when the fund strained, the body chose seven men and ordained them; and Ellen White draws the design rule: “The organization of the church at Jerusalem was to serve as a model for the organization of churches in every other place” (The Acts of the Apostles, p. 91). For this movement she is more explicit still: the representative body assembled in General Conference is the highest authority God has on earth (Testimonies, vol. 9, pp. 260–261), the tithe is to go to “the one to which the Lord has said it should go” (9T 249–250), and when a believer asked her personally where that was, she answered: the conference where you live (Letter 96, 1911). The appointment is not missing; it is simply made the way God makes appointments in a priesthood-of-believers church — through the body, as at Jerusalem.
Last, notice that God's direct judgment of His ministers has not lapsed either — He still purifies the sons of Levi (Malachi 3:3), on His schedule, as He always did; the absence of visible fire is not the absence of ownership. And the objection's edge cuts its own side twice as deep: if the conference lacks divine appointment for want of a naming miracle, the independent ministry lacks it doubly — it has neither the miracle nor the body's commission. An argument that dissolves every possible storehouse dissolves every possible alternative first.