How do you like your Christianity?
Ordered, spontaneous, learned, heart-warming, traditional, experimental, moral, or choral?
Excruciating is likely not how you want it.
"Excruciating" comes from the Latin excruciare "to torture, torment, afflict, harass" which was formed from cruciare "to cause pain or anguish," literally "to crucify" (from crux, "cross") to which was added the prefix ex- which is here used in the sense of "thoroughly".
The apostle Paul ask the Corinthian church: Is Christ divided? (1 Corinthians 1:13)
If so, that should be painful - "painful" as in "thoroughly painful". If we don't feel the pain, we have lost our senses.
When does Christianity become excruciating? When the cross of Christ is taken out of it, taken the prefix ex- in its other sense as "out".
On the cross the power of God's love was shown to be greater than our love for power. Where the cross is pushed aside, the love of power takes hold in the church and divides it.
The cross is a place of shame and dishonour. Cicero: "The very word ‘cross’ should be far removed not only from the
person of a Roman citizen but from his thoughts, his eyes and his ears." (Pro
Rabirio Perduellionis Reo 5.16). Where the cross is pushed aside, the love of prestige takes hold in the church and divides it.
Christ's cross is the place of reconciliation, between God and us and between people. Where the cross is pushed aside, enmities remain and the church is divided.
When the cross (crux) is taken out of (ex) Christianity, Christ is divided, Christianity becomes excruciating.
