Words as Signs

What Augustine Can Teach Us About Biblical Interpretation

It is no secret that Augustine’s On Christian Doctrine influenced biblical interpretation for centuries to come. He influenced, for example, Thomas Aquinas, a Roman Catholic, and William Whitaker, a Protestant who influenced the formulation of Westminster Confession of Faith 1.9.[1] If we want to understand why Christians have interpreted the Bible in the past the way they did, we must recognize and understand the influence of Augustine.

I will attempt to identify some of the most basic elements of Augustine’s influence upon subsequent interpreters. Though his influence on biblical interpretation is more involved than what will be discussed, his discussion on words as signs is probably his most important contribution and can be helpful to us today.

Let’s consider briefly Augustine’s theory of words as signs, or his philosophy of signs. Note well that Augustine’s philosophy of communication is not derived exclusively from Scripture. The illustrations he uses often come from nature, or creation, and our everyday interaction with it. This illustrates Augustine’s use of “philosophy” as a handmaiden to theology. Augustine also utilized metaphysics (in this case meaning “beyond the physical”) to help chasten or purify his view of Scripture interpretation. This is a lesson for us in our day, as some claim their metaphysic comes exclusively by virtue of what the written Word of God teaches about metaphysics. Yet it is naive to claim that we learn all metaphysics from Scripture and, therefore, bring no metaphysical commitments to Scripture.

It is important to recognize that words functioned as signs prior to the Word of God written. If they didn’t, how could the human authors of Scripture write Scripture in any intelligible fashion, and how could its initial readers understand anything at all about it? In fact, grammar predates the Word of God written. Philosophy of language is first learned outside of Scripture then brought to Scripture, not the other way around. This applied to Scripture’s human authors and its initial readers, as well as all subsequent readers. Though Scripture does reveal the preconditions necessary to account for grammar, we come to it with an understanding of grammar; therefore, linguistics predates the Word of God written. This means that accounting for linguistics is not exclusively a scriptural phenomenon. This is illustrated by Augustine’s examples from nature and his metaphysical musings upon them.

1. Signs in General

Augustine says, “All instruction is either about things or about signs; but things are learned by means of signs.”[2] In other words, while things acutally exist, they are learned by signs. When we read the word “tree,” we are reading a sign of a thing (i.e. the sign is the word “tree” which signifies a thing that exists, “tree”). Things can be signs of other things as well. For example, the sacrificial system of the Old Testament is a thing; it existed prior to being written about. But in that state of existence it was a sign of the sacrifice of Christ in virtue of its divinely intended “thingness,” as divinely indicated by subsequent words, which are themselves signs. Words are things which are signs of something else which, in turn, can be a sign of something else. Therefore, the words of Scripture concerning the sacrificial system of the Old Testament are signs indicating that the thing signified by the words signifies the sacrifice of Christ. Augustine puts it this way: 

No one uses words except as signs of something else; and hence may be understood what I call signs: those things, to wit, which are used to indicate something else. Accordingly, every sign is also a thing; for what is not a thing is nothing at all. Every thing, however, is not also a sign.[3]

The tree in your front yard is a thing, but it is not a sign of something else. But can trees also be signs? The answer is yes (e.g. the tree of life signified something other than mere treeness). It was a thing signifying another thing.

Augustine continues, “For a sign is a thing which, over and above the impression it makes on the senses, causes something else to come into the mind as a consequence of itself...”[4] He gives several examples:

  • A footprint, which signifies that someone stepped where the observer is looking, though the footprint does not necessarily identity the person who made the print by walking)
  • Smoke in the air above (which signifies a fire below, though the smoke does not necessarily identify a particular fire)
  • A trumpet sounding in a battlefield, which signifies that soldiers need to advance. However, the sound of a trumpet in a battlefield signifies something it does not in a concert hall. This indicates that signs are to be interpreted contextually.

 2. Natural Signs

Augustine defines natural signs as follows:

...those which, apart from any intention or desire of using them as signs, do yet lead to the knowledge of something else, as for example, smoke when it indicates fire. For it is not from any intention of making it a sign that it is so, but through attention to experience we come to know that fire is beneath, even when nothing but smoke can be seen.[5]

Interpreting smoke as a sign of fire is not due to the intention of either the smoke or the fire from which it comes; it is due to our experience with smoke and fire, the relation between the two, and our memories and shared ways of drawing conclusions from our observations.

As a footnote to this discussion, let me ask a question: Given the real, or actual, existence of a particular fire, when you see its smoke and conclude a fire must exist, is your knowledge corresponding to reality? In other words, do at least some of our observations of nature give us true knowledge of what really exists? If that is the case—and it is—then our knowledge of the fire under discussion presupposes that created effects have created causes (i.e. the smoke is caused by the fire and the fire was caused by something other than the smoke). Our conclusion to the observation of the presence of smoke is that a fire exists causing the smoke to appear.

Though we do not consciously trace all effects back to their causes, it is the intuitive process which takes place in our minds. This is not a discursive activity of the mind (i.e. proceeding by reasoning or argument rather than intuition). When we see smoke, as in the illustration above, we do not say to ourselves:

  1. Some particular smoke exists.
  2. All smoke is caused by some particular fire.
  3. Therefore, a particular fire exists.

In other words, our conclusion that a particular fire exists does not come to us by virtue of a discursive process. It's intuitive to the human subject while observing nature that created effects have created causes. You probably did not realize how much can be learned by analyzing the presence and recognition of smoke. This should alert us to the fact that hermeneutics (i.e. interpretation of language and texts) involves a philosophy of mind and general ontology or metaphysics, both of which are brought to Scripture in order to understand Scripture. 

3. Conventional Signs and Visible Words

Augustine makes a further point:

Conventional signs...are those which living beings mutually exchange for the purpose of showing, as well as they can, the feelings of their minds, or their perceptions, or their thoughts.[6]

A non-verbal, conventional sign in our day would be the peace-sign made with the index and middle fingers of one of our hands. The peace-sign would be, in the thought of Augustine, a visible word. Other examples of visible words include nodding and hand gestures.[7] And yet the most important signs are words: “For among men, words have obtained far and away the chief place as a means of indicating the thoughts of the mind.”[8]

4. Proper and Figurative Signs

Augustine distinguishes between proper and improper (i.e. figurative) signs. Proper signs “point out the objects they were designed to point out, as we say bos [a genus of domestic cattle] when we mean an ox, because all men who with us use the Latin tongue call it by this name.”[9] Something similar to this would be our use of “man’s best friend,” when we mean dogs.

Figurative signs use the proper names of things “to signify something else...”[10] Augustine gives the following example:

...as we say bos, and understand by that syllable the ox, which is ordinarily called by that same name; but then further by that ox understand a preacher of the gospel, as Scripture signifies, according to the apostle’s explanation, when it says: “Thou shalt not muzzle the ox that treadeth out the corn.”[11]

Augustine understands that “ox,” in the context of 1 Corinthians 9, is not used properly but figuratively, referring to gospel preachers (cf. 1 Tim. 5:18). The sign, “ox,” signifies gospel preachers. The word “ox,” properly considered, is a verbal sign of a big animal. But the word “ox” in the context of Paul’s argument signifies gospel preachers.

Paul uses the word "ox" figuratively, but in its original context (Deut. 25:4) the word is used properly. Paul takes the Deuteronomy text, which is about actual oxen, and applies it to preachers.

Something of vital interest is going on here, something that we can see more clearly with a question: Does Paul use “muzzle” properly or figuratively?

Paul uses "muzzle" figuratively, because muzzling an ox entails not allowing him to eat part of the effect of his work. Muzzling a preacher, however, means to not pay him his due. It therefore seems best to understand Paul as extracting a principle of equity from the Deuteronomy text and applying it to preachers. This seems to be the case by his words immediately following the Deuteronomy quote:

God is not concerned about oxen, is He? Or is He speaking altogether for our sake? Yes, for our sake it was written, because the plowman ought to plow in hope, and the thresher to thresh in hope of sharing the crops. If we sowed spiritual things in you, is it too much if we should reap material things from you? (1 Cor. 9:9b-11)

Here we have an example of Paul using an Old Testament text, originally revealed in a proper sense, in a figurative manner. This indicates to us that some Old Testament texts in their proper sense actually contain, implicitly, a figurative sense. The proper sense is an application of a more basic principle. In other words, Deuteronomy 25:4 is an application of a more basic principle than the words used to originally annunciate it. That more basic principle is a principle of equity derived from the eighth commandment: “You shall not steal.”


This brief study highlighted Augustine’s theory of the function of words as signs. Words, according to Augustine, are the most important signs, though not the only signs. Things can be signs, or visible words. The concept of things as signs, or visible words, helped the Christian theological tradition articulate the function of the sacraments of baptism and the Lord’s Supper, for example. Both baptism and the Lord’s Supper are signs signifying something other than the things they are. They are visible words, in that they convey meaning to those informed by the Holy Scriptures.

Of the many influential things Augustine’s On Christian Doctrine contains, his study of words as signs was and continues to be of great importance.

Richard Barcellos is pastor of Grace Reformed Baptist Church, Palmdale, CA, and Associate Professor of Exegetical Theology at IRBS Theological Seminary. He is the author of Getting the Garden Right: Adam’s Work and God’s Rest in Light of Christ.

Related Links

Theology on the Go: "Theological Retrieval for Evangelicals"

"On Informed Reading" by Richard Barcellos

Reformed Catholicity, edited by Michael Allen & Scott Swain 

Reformation: Yesterday, Today and Tomorrow by Carl Trueman

"Six Benefits of Studying Church History" by William Boekestein

"An Authoritative Appeal to Tradition?" by Jeffery Waddington


[1] See David S. Sytsma, “Thomas Aquinas and Reformed Biblical Interpretation,” in Manfred Svenson and David VanDrunen eds., Aquinas among the Protestants (Oxford, UK: Wiley Blackwell, 2018), 62-63.

[2] Augustine, On Christian Doctrine, in NPNF, First Series, vol. 2, ed. Philip Schaff (1887; reprint, Peabody, MA: Hendriksen Publishers, Fifth printing, 2012), I.ii.2.

[3] Augustine, On Christian Doctrine, I.ii.2.

[4] Augustine, On Christian Doctrine, II.i.1.

[5] Augustine, On Christian Doctrine, II.i.2.

[6] Augustine, On Christian Doctrine, II.ii.3.

[7] Augustine, On Christian Doctrine, II.iii.4.

[8] Augustine, On Christian Doctrine, II.iii.4.

[9] Augustine, On Christian Doctrine, II.x.15.

[10] Augustine, On Christian Doctrine, II.x.15.

[11] Augustine, On Christian Doctrine, II.x.15.


On YouTube

The Story of Scripture

Find Out More

Register for the Philadelphia Conference on Reformed Theology

Reformed Resources

2023 Annual Report