oikodomē

In everyday Greek this was a plain construction word for a building, the thing masons put up. The Gospels keep exactly that sense: when the disciples marvel at the great stones of Herod's temple, they are pointing at real architecture, and Jesus warns that not one stone will be left on another.

Paul stretches the same word into an image. He calls the Corinthian church "God's building," a structure still being raised, and in Ephesians "the whole building, joined together, grows into a holy temple." Here the building is people, fitted together like stones into a house for God. The nearby words fill out the picture: the common word for a οἶκος is an ordinary house or household, while the sacred result Paul has in view is a ναός, the inner sanctuary where God dwells. In Ephesians the phrase can be read word for word as "every building," but because it grows into one holy temple, translators render it "the whole building."

One use looks past this life altogether. In 2 Corinthians Paul sets the fragile "tent" of the mortal body against a lasting "building from God, a house not made with hands, eternal in the heavens." What that heavenly building is remains one of the debated points in his letters.

This is Paul's signature use of the word, and it is almost entirely his own. Outside the Bible, Greek never used this noun for the shaping of people; it meant bricks and mortar. Paul built the new sense from the prophets, above all Jeremiah's promise that God would "build and plant" his people rather than tear them down. From that he made "building up" a word for everything that makes a church grow.

The building up is corporate, not private. When Paul prefers clear prophecy to unintelligible tongues, or weighs how believers speak and behave, the test is always whether the gathered community is strengthened, not just the individual. "Let everything be done for building up," he says of worship, and each believer is to please the neighbor "for building up."

He even defines his own authority this way. Echoing Jeremiah once more, he says his authority was given "for building up and not for tearing down," so that even his sharpest correction is claimed as construction work. The related verb οἰκοδομέω carries the same double life, used both for putting up a house and for strengthening a person or a church.