The Latin phrase in saecula saeculorum expresses the idea of eternity and is literally translated as "unto the ages of ages."

The phrase is the Vulgate translation of the New Testament, translating the original Koine Greek phras "e "εἰς τοὺς αἰῶνας τῶν αἰώνων" (eis toùs aionas ton aiṓnōn) e.g. Phillippians 4:20. The phrase expresses the eternal duration of God's attributes. Other variations of the phrase are found in e.g. Eph 3:21

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