Pastor Russell never claimed to originate Bible truths, but to recover truth held by the early church. In his own words (from the May 1899 Watchtower, pages 86 & 87, (Reprint #2453):
“We found that for centuries various sects and parties had split up the Bible doctrines amongst them, blending them with more or less of human speculation and error; and that the misplacement of the truth frequently made of it gross error. We found the important doctrine of justification by faith and not by works had been clearly enunciated by Luther and more recently by many Christians; that divine justice and power and wisdom were carefully guarded tho not clearly discerned by Presbyterians; that Methodists appreciated and extolled the love and sympathy of God; that Adventists held the precious doctrine of the Lord’s return; that Baptists amongst other points held the doctrine of baptism symbolically correctly, even tho they had lost sight of the real baptism; that some Universalists had long held vaguely some thoughts respecting “restitution.” And so, nearly all denominations gave evidence that their founders had been feeling after truth: but quite evidently the great Adversary had fought against them and had wrongly divided the Word of God which he could not wholly destroy.
Our work since has been to bring together these long scattered fragments of truth and present them to the Lord’s people–not as new, not as our own, but as the Lord’s. So far from desiring to make something new, we are most careful to avoid both in letter and spirit either taking from or adding to the Word of the Lord; for we are fully convinced that “the Word of God is sufficient,” “that the man of God may be perfect, thoroughly furnished unto all good works.”– 2 Tim. 3:17 …
But as we claim that what we present is not our own, not new, but “The Old Theology”–so old that it had been lost sight of for centuries–we must disclaim any credit even for the finding and rearrangement of the jewels of truth. “It is the Lord’s doing, and it is marvelous in our eyes.” The writer wholly disclaims superior ability or qualification for the reorganization of the truth in its present solidarity. As the time had come for the bringing together of the scattered thoughts of past centuries in the marvelous inventions of our day,–so the time had come for the bringing together of the fragmentary hopes and promises of God’s Word scattered through Christendom. To deny that the Lord has simply “poured out” this harvest time blessing of “present truth” in his own due time and in his own way, would be as wrong as to claim it as of our own invention…”