Jesus strongly warned that riches can keep people from entering the kingdom of God. In Palestine, the camel was the largest animal, and the eye of a needle was the smallest opening. Jesus used this picture to show how difficult it is for rich people to follow him.
Even so, some rich people did follow Jesus. Still, more of the followers of Jesus came from the poor than from the rich.
Some people say that the eye of the needle was a small gate in Jerusalem’s wall. But this explanation is not convincing. There is no evidence that such a gate ever existed. It also ignores how Jesus commonly used hyperbole (intentional exaggeration for emphasis) in his teaching (see also Matthew 7:3–5; 23:24).