Can a company claim to be an assembly and still have doctrinal errors?

Can a company claim to be an assembly of God, where Church truths and fundamental truths are not taught?

Of course, we understand that such truths are not denied, but simply neglected for others, such as exhortation, or prophetical and dispensational teaching. Where fundamental truth is generally denied in a company, such loses its character as an assembly, just as the individual does his character as a Christian. But what constitutes an assembly, is a company of true believers who seek to gather to the Name of the Lord, know no other Centre than He, and no other Leader than the Spirit of God (while welcoming those whom He has called to rule, or qualified to minister the Word), and no other rule than His Word.

But why should not these truths be taught? Are there not elders among the saints, who though not exactly “teachers,” in the sense of possessing a distinct gift, are nevertheless “apt to teach” (1 Timothy 3:2) and able to explain both church and fundamental truths? There is a call for prayer that the Lord would raise up “gifts” in His churches able to instruct the saints. But it is not “light” which constitutes an assembly, but life in Christ of those composing it.

On the other hand, we need “all the counsel of God” as revealed in His Word, not merely certain favourite truths, for “all Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God may be perfect, throughly furnished unto all good
works” (2 Timothy 3:16, 17).