Berean Study Bible
being fully persuaded that God was able to do what He had promised.

King James Bible
And being fully persuaded that, what he had promised, he was able also to perform.

American Standard Version
and being fully assured that what he had promised, he was able also to perform.

Darby Bible Translation
and being fully persuaded that what he has promised he is able also to do;

Douay-Rheims Bible
Most fully knowing, that whatsoever he has promised, he is able also to perform.

English Revised Version
and being fully assured that, what he had promised, he was able also to perform.

Young's Literal Translation
and having been fully persuaded that what He hath promised He is able also to do:

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