Owen Barfield regarded himself as a disciple of Rudolf Steiner - in a not-altogether healthy way; because it exerted a constraining effect on his potential and caused Barfield to leave out - unexplained - considerable aspects of his world view.
Instead Barfield, at a certain point, would merely recommend his audience to 'read Steiner'; which is, for most people, way too much to ask; since locating and extracting the undoubtedly gold insights from Steiner's voluminous dross of error and nonsense is the work of several years hard labour...
I speak as one of not-many of Barfield's great admirers who actually have put-in these years of work. Having done so; I was rather surprised to find that Barfield makes a very noticeable change to Steiner's terminology from The Philosophy of Freedom (insights from-which form an essential basis to Barfield's schema as expressed in (for example) Saving the Appearances, Unancestral Voice, Speaker's Meaning and History, Guilt and Habit.
How do we attain knowledge of reality, and is such knowledge indeed possible? This question forms the basis of that branch of 'modern' (post-medieval) philosophy called epistemology.
However, the modern attempt to make epistemology fundamental (as does so much 19th and 20th century philosophy) is actually an error, and has gone nowhere.
Nowhere; because epistemology takes-for-granted the primary level of philosophy, which is metaphysics: that discourse which tries to describe our most fundamental assumptions about the nature of reality.
Thus, both Steiner and Barfield fail to describe their primary assumptions about reality before they embark describing their model of knowledge - which has the effect of giving these models a rather arbitrary, take-it-or-leave it quality.
(For instance, both Steiner and Barfield ought to describe what they assume about God before they describe what they believe about knowledge; since for them both the possibility of knowledge depends on a personal creator God who has certain attitudes towards Men.)
Nonetheless, since I share broadly the same metaphysical assumptions as Steiner and Barfield, I regard their models of knowledge as very useful - which is all that can reasonably be asked of any simple model of reality; especially one that aims at a time-less hence 'static', cross-sectional description of reality.
The following is a comparison of the terminological equivalents of the epistemological models of Steiner and Barfield:
Percept + Concept = Thinking
Perception + Thinking = Consciousness
The potential confusion when reading these authors is that they use thinking to mean different things: Steiner's thinking is the end result of our perceptions of the world being understood and interpreted by concepts.
But for Barfield, thinking is (more or less) what Steiner means by concepts': the processes by which we understand and interpret perceptions - or 'images' in the case of ancient Man, whose perceptions came packaged with meanings.
Steiner thus talks a lot about 'thinking' of a particular kind (e.g. 'pure' thinking, or 'heart-thinking') as being the main aim of modern Man; the destined path ahead. This thinking (says Steiner) can be cultivated by meditative exercises which are intended to (but actually do not!) promote the desired kind of thinking. The desired kind of thinking is itself True Knowledge - and this is therefore Steiner's epistemology.
By contrast; Barfield talks about the destined and desirable future state of Consciousness; which is self-aware, active and chosen (rather than unconscious, passive and automatic): he calls this Final Participation; and for Barfield this is True Knowledge - as well as the proper aim of created Man (because Final Participation is to join with God in the work of creation).
After struggling to 'get' this for a few years; I think the above equivalence is broadly correct; and might be helpful to those who wish to read both Steiner and Barfield.