What is the difference between “Testament” and “Covenant”? In the Western world, many people are familiar with a “final will and testament” — a legal document read when someone passes away. The document expresses the deceased’s wishes, often in connection with estate and inheritance. As a unilateral declaration of one’s will, a “testament,” in this sense, is not the same as a “contract” or “pact,” which necessitates an agreement between two or more parties. The author of Hebrews makes an appeal to this Greek term to show that a “testament” (διαθήκη; diatheke) is initiated only after death (Heb 9:16-17).
The English theological term “New Testament” comes from the Latin Novum Testamentum – The Latin for “New Testament” translates the Greek phrase καινὴ διαθήκη (kaine diatheke) that appears in the Septuagint (Jer 31:31 LXX; cf. Lk 22:20). Yet, upon closer examination, the original Hebrew term for “covenant” (בְּרִית; berit) does not line up exactly with the idea of “testament” (διαθήκη; diatheke). So why would this Greek word be used in Luke, Hebrews and 1 Corinthians (Lk 22:20, Heb 8:8; 9:11–15, Cor 11:25)? Hard to say, but perhaps they merely followed in the footsteps of the translators of the Jewish Bible into Greek who felt that this was the best word to translate the Hebrew “covenant” (בְּרִית; berit). But translations are the work of human authors.
Indeed, a “testament” is quite different from the English term “covenant” — a word that comes from the Latin convenire, meaning “to come together,” “meet,” or “agree.” In Hebrew, the concept of a “covenant” (בְּרִית; berit) denotes making an agreement or treaty through interaction, most often by “dining together” (בָּרָה; barah; cf. Gen 26:28-29; 31:51-54). Except for a few biblical instances, covenants usually include specific terms, conditions, and obligations for each participant. The theological concept of a “New Testament” comes from Jeremiah 31:31-34, originally expressed in Hebrew and only later translated into Greek. Ultimately, all uses of the Greek term in the apostolic writings originate with Jeremiah’s “new covenant” (בְּרִית חֲדָשָׁה; berit hadashah) even though the first-century authors drew from the Greek Bible translation (LXX).
So, should English readers be referring to a New Testament or New Covenant? Since one cannot enter into a mutual agreement that is unilateral, “New Testament” would be something of a misnomer. On the other hand, covenants in the Bible are made “with” and “between” parties (e.g., Gen 6:18, 9:17, 17:10; Deut 29:12; 1 Kgs 8:21, 15:19; 2 Sam 23:5). Thus the term “covenant” is a much more accurate choice to express this biblical idea.