katabolē

At root this word names the act of laying something down so as to set it up:

• laying the base of a building
• founding a city or an institution
• putting money down as a deposit

In the New Testament it appears in this branch of its meaning inside one fixed phrase, "the foundation of the world," which Greek-speaking Jews had coined as a shorthand for creation. So in these ten verses the word is not talking about a wall or a footing; it points to the moment God brought the ordered world into being, the starting line from which everything else is measured.

The phrase comes in two forms, and the small difference matters. Seven times it reads "from the foundation of the world," marking something that has held true across history ever since creation:

• hidden truths
• the kingdom prepared for God's people
• the blood of the prophets going back to Abel
• God's finished works
• the once-for-all death of Christ
• the book of life

Three times it reads "before the foundation of the world," reaching back past creation into God's own eternal life:

• the Father's love for the Son
• the choosing of believers
• the Son marked out as the sacrifice before time began

The one word stays the same; "from" places an event inside history, while "before" places it in eternity, before anything was made.

One warning belongs here, because it is widely repeated. A popular claim holds that this word really means "disruption" or "overthrow," so that "the foundation of the world" hints at some catastrophe that wrecked an earlier creation. Every standard reference work rejects this. In the Greek of the period the word overwhelmingly means "founding," not "ruin," and the only time it appears in the Greek Old Testament it describes a builder laying out a house. The idea that it means "disruption" comes from misreading a related verb back into the noun, and no serious scholarship supports it.

The same underlying idea of laying something down carries the word into a very different setting once in the New Testament. Paired with the word for seed, it was a fixed expression in ancient medical and everyday Greek for the male's part in conceiving a child, the laying down of seed that starts new life. Writers of the day used it exactly this way when describing how offspring come to be.

This is why the single verse where it occurs, a sentence in Hebrews praising the faith that made a childless couple able to have a son, is one of the hardest in the letter to translate and to pin down. The expression normally describes what the father contributes, yet the sentence names Sarah, the mother. Translators handle the tension in different ways, some rendering it as Sarah receiving power "to conceive," others as Abraham receiving power to father a child with Sarah named alongside him. The core image, though, is settled: seed laid down so that life may begin.