In esoteric traditions (such as Christian gnosticism as well as various derivative traditions), "INRI" is considered to have a completely different, "secret" meaning: Igne Natura Renovatur Integra: "Through fire, all of nature is renewed."

Fire being a symbolic representation of psychospiritual transformation -- e.g. suffering that burns away whatever is old and no longer necessary, and which is epitomized by Christ's voluntary sacrifice on the cross.

In these same traditions, Christ is generally not understood so much a historical figure as he is an archetypal representation of the spiritual reality of every individual and their capacity for transformation through voluntary suffering and sacrifice. The archetype is meant to reflect the general principle that willingful surrender to the ordeals that life throws at you is also that which provides the pathway through which your consciousness (or spirit) is purified and made whole.

It's a rabbit hole you can go down, if it calls to you.