The answer is: Eye of a needle

Mark 10:25

In Mark 10:25, Jesus uses a vibrant metaphor that would have resonated deeply with His audience: "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." At first glance, this hyperbolic expression seems comically impossible, drawing strong imagery from the impossibility of jamming a massive creature through a tiny sewing needle's eye.

Interestingly, history dissects this analogy in several ways. Some interpretations suggest there might have once been a narrow city gate called the "Eye of the Needle" through which camels could pass—but only if laden burdens were removed first. This interpretation presents a poignant spiritual truth: sometimes, wealth can be a burden demanding divestment before entering a more sublime spiritual existence.

Moreover, looking at the world Jesus lived in, it's essential to note that possessions often held proponents' allegiance, not just wealth itself. The rich young ruler earlier in the passage was challenged to sell his belongings to truly follow the teachings of Jesus. Beyond material wealth, this parable also invites ponderings on what 'riches' truly mean. It pushes individuals to consider their attachments and barriers that keep them estranged from deeper spiritual truths.

The use of an exaggeration like the camel invites us to marvel at the inconceivable yet compassionate generosity of a spiritual journey every person can partake in, regardless of their status or policies of exclusion. It’s a rich call to humility and reassessment of our personal affiliations with material pursuits on our way toward more profound understanding.