We are a sheltered culture. We are surrounded by all sorts of violence in media, we see war in distant nations brought home to us by network or streaming news services, sometimes we experience random criminal violence with the multiple shootings that seem to have become part of North American life.
But we are still VERY sheltered.
First century Judaea (and other parts of the Pax Romana) got to see first hand how nasty Rome could get enforcing that peace. Riots in the street and claims of police brutality? Under Roman Imperial practice, the police would not have used tear gas and rubber bullets, they would have used tanks, live rounds, and yes, even flame throwers. Would they have cared if innocents got caught in the crossfire? No, they would not, and would view that as cementing their point further. Cancel culture? Rome's idea of cancellation was exile outside the Empire for the fortunate and a very public and messy death for the less fortunate. The January 6, 2021 insurrection? Rome would have gone in and slaughtered all of them whether they were innocent or guilty. Any survivors would have been strangled or beheaded if citizens, and crucified if they were not. Ringleaders would have been publicly humiliated prior to a very slow execution, and if non-citizen that humiliation would have been very bloody.
So when St. Thomas was told, "We have seen the Lord!" he was justifiably skeptical. As any inhabitant of one of the more unruly Roman Provinces, he knew that Jesus, who was not a Roman citizen, would not have been allowed to survive His injuries. The scourging would have been a near-death experience (and may well have contributed to His rapid death on the cross due to blood-loss and exhaustion and likely opportunistic infection). The crucifixion was guaranteed the most gruesome way to die imaginable (the Latin word actually means "to apply torture"). If that was not enough, the Romans overseeing the crucifixion, stymied that He might already be dead, speared Him in the side to confirm that indeed post-mortem lividity was already setting in.
Doubting Thomas? More like No-Illusions Thomas. He like all the rest of his culture was NOT sheltered and knew the score. Jesus could not have survived His injuries. The evidence was overwhelming. So St. Thomas challenged the other Ten Apostles (and likely the other witnesses who were starting to stack up like cord-wood) that he was calling their bluff. Only a very alive Jesus standing in front of him and whose body AND WOUNDS could be physically inspected would convince St. Thomas that these witnesses were not hysterical or chemically augmented.
Our Lord, for some reason, saw fit to let St. Thomas stew for a while before appearing again. Rather than appearing to St. Thomas in isolation and perhaps leading the skeptical Apostle to believe he dreamed the encounter or had eaten some bad fish sauce, Our Lord made the visit when all eleven Apostles were together.
"Gobsmacked" might be a good term for St. Thomas' reaction. "Blown away" would be another.
Regardless, Our Lord went right up to the (probably by now bug-eyed and slack-jawed) doubting Apostle and without even addressing him by name told him to commence with the physical examination. The move was a subtle and as nuanced as using napalm for bug spray. St. Thomas, understandably, could not even stand at this point, and could only squeak out the only thing possible, the confession of what was truly in front of him, his Lord and his God.
Our Lord restored St. Thomas' faith in the most direct way possible. This man was to carry His Gospel to Persia and to India, far FAR away from any reasonable support network afforded to the other Apostles, and his faith had to be rock solid. Yet Our Lord also made note that He would not make personal visits to everyone, but gave the greater honour to those who would believe the Gospel and believe the Resurrection without the direct evidence. Yet because of St. Thomas' personal encounter with his Risen Lord, and because of the personal encounters of the rest of the Eleven, of St. Mary Magdalene, St. Cleopas and his companion on the road to Emmaus, the rest of the disciples in Jerusalem, Our Lord's Mother, and even as one late in time as St. Paul, we have an unshakeable witness that Our Lord Jesus defeated the hold of death and corruption and that His Gospel is unshakeable.
Blessed indeed are those who have not seen, but still believe the words of those who did. Thanks be to God.