GOD'S WORD® Translation
Brothers and sisters, let me use an example from everyday life. No one can cancel a person's will or add conditions to it once that will is put into effect.

American Standard Version
Brethren, I speak after the manner of men: Though it be but a man's covenant, yet when it hath been confirmed, no one maketh it void, or addeth thereto.

Berean Study Bible
Brothers, let me put this in human terms. Even a human covenant, once it is ratified, cannot be canceled or amended.

Douay-Rheims Bible
Brethren (I speak after the manner of man,) yet a man's testament, if it be confirmed, no man despiseth, nor addeth to it.

English Revised Version
Brethren, I speak after the manner of men: Though it be but a man's covenant, yet when it hath been confirmed, no one maketh it void, or addeth thereto.

King James Bible
Brethren, I speak after the manner of men; Though it be but a man's covenant, yet if it be confirmed, no man disannulleth, or addeth thereto.

World English Bible
Brothers, speaking of human terms, though it is only a man's covenant, yet when it has been confirmed, no one makes it void, or adds to it.

Young's Literal Translation
Brethren, as a man I say it, even of man a confirmed covenant no one doth make void or doth add to,

Galatians 3:15 Additional Translations ...