The term brothers in this context should be understood as “fellow Christians” or “fellow believers in Christ.”

I am going to use an everyday example is literally “I speak according to man” or “as men do.” The meaning here is simply that Paul is going to talk about something that is of common knowledge to his readers (Jerusalem Bible “compare this with what happens in ordinary life”; New English Bible “let me give you an illustration. Even in ordinary life…”). One may also translate as “I’m going to compare God’s promise with something that happens all the time,” or “What I have been talking about is similar to what you yourselves know about.”

When two people agree on a matter and sign an agreement represents the Greek “a covenant (or, a will) once ratified, though it be man’s….” The differences in various translations stem from the problem of how to translate the term which Good News Translation renders here as “agreement,” since it is the more natural word in this context; but in verse 17 Good News Translation renders the same word as “covenant,” since it is the more natural word in that context. Does this word mean “will” (“testament”) and involve only one man (Revised Standard Version “a man’s will”; Jerusalem Bible “a will”; New English Bible “a man’s will and testament”)? Or does the word get its meaning from the Hebrew concept of “covenant” (“contract”) and accordingly involve two participants (compare Phillips “once a contract has been properly drawn up and signed…”)? The biblical usage of the term and the overall context favor the latter alternative. It is true that in classical Greek, and in some later Jewish writers like Josephus, the term is used in the sense of “will” or “testament.” Furthermore, the use of “inheritance” in verses 18 ff. seems to suggest this meaning. However, these arguments are offset by stronger ones in favor of “covenant.” The biblical usage of the term is in the sense of an agreement between two parties, sometimes between two men or two nations, but in most cases, between God on the one hand and a person, group of persons, or a nation on the other. Furthermore, in the Septuagint, the Hebrew word for covenant is rendered with the same Greek word here in question. There is little doubt that even in the New Testament, with one or two exceptions, the word used is equivalent to the Hebrew word for “covenant.” Still further, the same word is used in verse 17, and there it clearly means “covenant,” since to translate it “testament” or “will” would imply the death of God before the testament goes into effect! Regarding the argument that wills were irrevocable during those days, the evidence is inconclusive as to whether Greek wills could be included in this category. To the argument that Paul’s Gentile readers would understand the term to mean “will” and nothing more, it should be noted that Paul is here arguing against Jewish Christian adversaries, and therefore Paul used terminology which was familiar to them. It is likely that the terminology was also familiar to the Gentile Christians in Galatia because of the raging controversy in which they were involved.

Agree and sign render a Greek legal word which could be translated “ratified” (Revised Standard Version) or whatever is done to an agreement in order to give it legal force (New American Bible “legally validated”; New English Bible “duly executed”; Phillips “properly drawn up and signed”). Expressions such as agree and sign in reference to an agreement, covenant, or contract may be expressed in a number of different ways, some quite idiomatic, for example, “tie themselves together,” “cut an agreement,” “snap fingers together,” “touch one another concerning,” or “eat with one another about.”

No one could be understood either as referring to an outside party (Phillips “can neither be disregarded nor modified by a third party”) or to anyone, including the parties to the agreement. Mutual agreement for either annulment or amendment is, of course, always possible, but is not important to the force of the illustration. In order to emphasize the fact that one person on his own initiative cannot alter such an agreement, one may say “no one alone can break the agreement,” or “no one person just because he wants to can break the agreement.”

Break is to “violate” or “disregard” (Phillips, Jerusalem Bible) or to “set aside” (Knox, New American Bible, New English Bible). The Greek word, however, can also mean “annul” (Revised Standard Version), that is, to declare it legally not binding. To break an agreement or covenant may be expressed in a number of different ways, for example, “to throw an agreement away,” “to forget an agreement,” “to wipe out a covenant,” or “to say that a covenant has become nothing.”

Add anything to it translates a Greek word which is used in the New Testament only here. It means “to make additional prescriptions.” This may be rendered as “add other words to it” or “make more requirements in it.”

Quoted with permission from Arichea, Daniel C. and Nida, Eugene A. A Handbook on Paul’s Letter to the Galatians. (UBS Handbook Series). New York: UBS, 1976. For this and other handbooks for translators see here .