Hebrews 6:13-17 - WEB
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For when God made a promise to Abraham, since he could swear by none greater, he swore by himself,
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saying, "Most surely I will bless you, and I will surely multiply you."
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Thus, having patiently endured, he obtained the promise.
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For men indeed swear by a greater one, and in every dispute of theirs the oath is final for confirmation.
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Wherein God, being determined to show more abundantly to the heirs of the promise the immutability of his counsel, interposed with an oath;
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