Exploring the Meaning of Metallasso in Greek

μεταλλάσσω expresses the act of exchanging, and it appears in Romans 1 in two closely linked statements about substitution—first in relation to “the truth of God,” and then in relation to “the natural function.” In both settings the word marks a decisive replacement of one thing with another within the argument of the passage.

Root and Related Words

Metallasso (μεταλλάσσω) is related to allasso (ἀλλάσσω), “to change” (Strong’s G236), and to meta (μετά), “with/after” (Strong’s G3326). In Romans 1 the verb’s force is heard where Paul describes a change that is not merely additive but involves one item being set in the place of another.

Occurrences

“who exchanged the truth of God for a lie, and worshiped and served the creature rather than the Creator, who is blessed forever. Amen.” (Romans 1:25)

Here μεταλλάσσω sits at the hinge between what is held and what is practiced. The object exchanged is “the truth of God,” and what replaces it is “a lie.” The verse then unfolds the practical outworking of that exchange: worship and service are redirected, not left empty. The new orientation is described in concrete terms—“worshiped and served the creature rather than the Creator.” The exchange therefore functions as a reassigning of allegiance: what belonged to God is transferred to what is created. By placing “the truth of God” and “a lie” on opposite sides of the exchange, the wording portrays a substitution that overturns the proper order named at the end of the sentence, where “the Creator” is contrasted with “the creature” and identified as “blessed forever.” In this sentence, μεταλλάσσω does not stand alone as an abstract description; it frames the following clauses as the enacted result of taking one object and putting another in its place.

“For this reason, God gave them up to vile passions. For their women changed the natural function into that which is against nature.” (Romans 1:26)

In the next verse the same basic idea is carried into the realm of “function.” The exchange is not described as a shift in opinion but as a change of “the natural function” into something characterized as “against nature.” The immediate setting begins with causation and consequence: “For this reason, God gave them up to vile passions.” Within that frame, μεταλλάσσω introduces a specific example marked by “For,” and the subject is explicit: “their women.” The exchange is expressed as an “into” movement—one function is altered so that it becomes another kind of function. The language of “natural” and “against nature” makes the replacement evaluative within the verse itself; the exchange is presented as a departure from what is called “natural” toward what is described in opposing terms. The verb thus serves to depict the action as an intentional transfer from one defined category to another, aligning the behavior with the “vile passions” just mentioned.

Sense and Usage

Across these two occurrences, “to exchange” is used to portray substitution with moral and theological weight. In Romans 1:25, the exchange is framed as trading “the truth of God for a lie,” and the clause that follows shows how such a trade reshapes worship: service is redirected from “the Creator” to “the creature.” The verse’s internal contrasts—truth/lie, creature/Creator—present the exchange as a reordering of what is valued and honored. The action is not depicted as losing the truth accidentally; it is described in transactional terms, as a replacement in which one thing is taken up in place of another.

In Romans 1:26, the exchange is applied to “function,” and the verb draws attention to the decisive character of the change: something “natural” is replaced by something “against nature.” The verse’s structure links this exchange to the preceding statement that “God gave them up to vile passions,” so that the exchange is not merely a private decision but part of an argument about the direction of passions and conduct. In both verses, μεταλλάσσω functions as a verb of replacement that helps Paul describe a movement from one defined object or pattern to its opposite. The exchange is depicted not as a minor adjustment but as a turning that creates a new object of devotion (Romans 1:25) or a new kind of practice (Romans 1:26).

The two occurrences also show how the verb can work with different kinds of objects. It can take an object as lofty as “the truth of God” and set it in exchange for “a lie,” or it can take something described in terms of “function” and depict it as altered into an opposing kind. In both cases, the exchange is intelligible because the verse itself names both sides of the transaction: what is given up and what replaces it. That rhetorical clarity is part of the word’s effect in this passage: the reader is not left to guess what has changed, because the sentence supplies the before-and-after within the same line.

Imagery

Romans 1 uses the imagery of exchange to depict a kind of transfer—truth traded for falsehood, and a defined “natural function” transformed into an opposed pattern. The picture created by these lines is of replacement: one thing is put down and another is taken up, and the results are visible in the redirected worship of Romans 1:25 and in the changed practice described in Romans 1:26.

Sources: Lexical data from Strong’s Exhaustive Concordance and the Translators Brief Lexicon of Extended Strongs for Greek (STEPBible, CC BY). Occurrence data from the Translators Amalgamated Greek New Testament (STEPBible, CC BY). Scripture quotations from the World English Bible (public domain).