Truth in any area of thought, whether in theology, philosophy, law, music, or education, must be understood in the form of an ellipse rather than a circle. An ellipse has two foci; a circle has one.
This means that truth is the sum total of its objective and subjective elements, the two foci in the ellipse. In music, for example, many find satisfaction primarily in objective elements such as harmony, unity, and order. Others seek music primarily for subjective reasons in that certain music expresses, or reflects, their feelings. Thus, one person may consider a particular piece of music as classical (Mozart) while another may classify it as expressionism (Beatles, rock, etc.). The point is that neither foci is the totality of truth. The human need for order, on the one hand, and the need for relevance and meaning, on the other, is the basic structure that truth is meant to satisfy.
In politics, we see the two focal points as socialism (collectivism) and free enterprise (democracy). In economics, the foci are Keynesian (government control) and free trade. In education, content-centered versus student-centered. In epistemology, idealism versus naturalism.
In theology, truth is the sum total of its objective and subjective elements. One focus is the emphasis on transcendence (revelation) and the other is immanence (human response, such as reason and feeling). To ignore the existence of the two foci in the theological ellipse makes the ellipse of truth into two circles. And the two circles have been arguing their particular point of view since Creation.
But Biblical truth unites the two circles within the ellipse of salvation. Thus, revelation with the authority of God's Word, meets our human need for meaning and relevance. Some call this interchange the objective, external Word meeting the subjective response of a person saying, "This truth is for me."
In other words, when someone appeals to the Bible as "truth" without an equal emphasis on personal meaning and relevance, we know that the ellipse has become two circles. On the other hand, when one appeals primarily to reason or feeling as the test of truth (human autonomy), we also know that the ellipse has become two circles.
Salvation truth binds together the objective will of God and the subjective "Yes" of a responsible (response-able) person. Even as water cannot be divided between hydrogen and oxygen and remain water, so the objective and subjective elements of salvation cannot be divided and yet remain "salvation."
For example, grace fulfills its task only when men and women of faith respond. Likewise, pardon/forgiveness comes only to those who comply with its conditions such as a sincere desire for power to overcome the evil for which the pardon is sought.
All the divisions between various churches within Christianity, and between Christianity and other world religions, occur when the ellipse is ignored. When one of the foci becomes the "circle of truth," we surely have a heresy (a partial truth that becomes a whole error).
For example: