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"The eye of a needle" is part of a saying of Jesus recorded in the synoptic gospels:

“I tell you the truth, it is hard for a rich man to enter the kingdom of heaven. Again I tell you, it is easier for a camel to go through the eye of a needle than for a rich man to enter the kingdom of God.” Matthew 19:23-24

Parallel versions appear in Mark 10:24-25, and Luke 18:24-25.

The saying was a response to a young rich man who had asked Jesus what he needed to do in order to inherit eternal life. Jesus replied that he should keep the commandments, to which the man stated he had done. Jesus responded, "If you want to be perfect, go, sell your possessions and give to the poor, and you will have treasure in heaven. Then come, follow me." The young man became sad and was unwilling to do this. Jesus then spoke this response, leaving his disciples astonished.

The "eye of a needle" has been interpreted as a gate in Jerusalem, which opened after the main gate was closed at night. A camel could only pass through this smaller gate if it was stooped and had its baggage removed. This story has been put forth since at least the 15th century, and possibly as far back as the 9th century. However, there is no evidence for the existence of such a gate.

Variations on this story include that of ancient inns having small entrances to thwart thieves, or a story of an old mountain pass known as the "eye of the needle", so narrow that merchants would have to dismount from their camels and were thus were more vulnerable to waiting brigands.

Some claim that "camel" is a Greek misprint; that kamilos (camel) was a misprint of kamêlos, meaning "rope" or "cable". ^[2]

More than a misprint, this is a case of misinterpretation. The original word didn't mean simply "rope", but it referred to a very specific kind of ropes: the mooring lines or hawsers, known for being very large and thick. This would make more sense of the words spoken by Jesus. There are still traces of this origin nowadays: in the port of Genoa, Italy, the dockworkers are known in the local dialect as "Camalli".^[3] The word itself is indeed a mutation from the Arabic Hamal which means Dromedary.