A name could mark God's promise
In the Bible, names often carry meaning. They can recall a birth, express a parent's hope, or point to a person's place in God's unfolding story. So when God gave someone a different name, it was not usually a casual nickname. It often made God's purpose visible.
Abram became Abraham when God confirmed his covenant with him. The new name looked ahead to the many nations that would come from Abraham's family, even though he and Sarah had waited a long time for a child (Genesis 17:5). Sarai's name also became Sarah as God promised that she would bear Isaac and become the mother of nations (Genesis 17:15-16). The change did not mean they had earned God's favour. It announced a promise God himself intended to keep.
Neither shall thy name any more be called Abram, but thy name shall be Abraham; for a father of many nations have I made thee.
A new name could follow a struggle
Jacob's story is especially personal. His earlier name was connected with grasping the heel at birth, and much of his life involved striving, deceiving, and trying to secure blessing for himself. On the night before meeting Esau again, Jacob wrestled through the dark until God gave him the name Israel (Genesis 32:24-28).
Israel became the name of Jacob's descendants too. Yet Jacob did not suddenly become flawless. He still had fears and failures. The new name showed that his future rested on God's blessing and that his life now belonged within God's larger purpose. God can meet people in their hard, honest struggles.
And he said, Thy name shall be called no more Jacob, but Israel: for as a prince hast thou power with God and with men, and hast prevailed.
Jesus named people for their calling
When Jesus first met Simon, Andrew's brother, he gave him the name Cephas, which John explains as Peter (John 1:40-42). Cephas is an Aramaic word, and Peter comes from the Greek word petros. Both point to a stone or rock.
Peter was often impulsive. He would later deny knowing Jesus, then be restored and entrusted with caring for Jesus' people (Luke 22:61-62; John 21:15-17). His name was not a reward for already being steady. It pointed to the person Jesus was forming him to become and to the part he would play in strengthening other believers (Luke 22:31-32).
And he brought him to Jesus. And when Jesus beheld him, he said, Thou art Simon the son of Jona: thou shalt be called Cephas, which is by interpretation, A stone.
Not every new name came from God
Sometimes people received different names because they lived under another empire. In Babylon, Daniel, Hananiah, Mishael, and Azariah were assigned Babylonian names by a palace official (Daniel 1:6-7). This was part of an effort to train them for the king's service and absorb them into Babylonian life.
Those imposed names did not erase their faith or identity before God. Daniel continued to pray to God even when it became dangerous, and God delivered him from the lions' den (Daniel 6:10; Daniel 6:22). So a changed name can have different reasons depending on the story. Read the surrounding passage and ask who gave the name, why they gave it, and what the story reveals about God.