Christianity says Jesus was a man born somewhere around 2000 years ago. This man was different from all other human beings who ever existed. Jesus was God as a human being. This was the only time God would ever become a person. It was a unique event in all of history. God came here and became a human being.
When God became a human being, He was just like us in every way. His body was just like ours. His mind was just like ours. Think for a minute about what that means. It means Jesus didn’t fully realize exactly who He was.
It’s not that God decided to come and “especially inhabit” a person. It’s that God became a human being. God was an infant. God was a child. God was a teenager. God was an adult.
God got sick. God got sad. God got mad. God had sexual urges and sexual feelings. God worried. God was just like us in every way, even to the point that He wondered what was going on. He realized He was somehow different than others but didn’t know exactly how. He struggled with this.
Christianity says Jesus was really God. He was not some part of God. He was not some offspring of God. He was not just a person who was especially close to God. Jesus was God Himself as a human being, just like us in every way.
But at the same time God was here on earth as Jesus, He was still God. There’s no way to explain how God could be Jesus but, at the same time, still be “up in heaven” as God. It’s a mystery. But Christianity says it happened.