But to them that are called (autoi de toi klhtoi). Dative case, to the called themselves. Christ (Criston). Accusative case repeated, object of khrussomen, both the power of God (qeou dunamin) and the wisdom of God (qeou sopian). No article, but made definite by the genitive. Christ crucified is God's answer to both Jew and Greek and the answer is understood by those with open minds.