The bishop said after residents saw the wreckage caused by the storm, they experienced suffering and deep sadness, but they also got right to work to help each other.
"The resolve to help one block, one parish at a time continues to be strong," he said.
When the storm began, the bishop kept vigil praying to the Blessed Mother with two Marian devotions: Mary, Star of the Sea and Our Lady of Prompt Succor.
"When the eye of the storm comes, all you can do is pray," he said.
Later he said he "surrendered" the future to God and went to bed. The next day, without power, he listened to the radio as Harvey stalled over his 10-county diocese and emerged from his home to find an incredible amount of damage.
In Galveston-Houston where Harvey idled and dumped up to 49 inches of rain, Father J. Phong Nguyen answered a desperate call for help. The parochial vicar at St. Vincent de Paul Catholic Church in Houston drove through the rain to a northwest Houston neighborhood flooding to "the tops of the garage."
On a rescue mission, the priest commandeered a boat after finding water too high to drive through and sped through the neighborhood. After bringing a family to safety with other rescuers, he heard more screams for help as they passed by more homes. For at least three or four hours -- Father Nguyen said he's unsure how long he helped because he made so many trips -- the priest helped pull stranded families from their second-floor windows and homes.
The priest said the water was 2 feet when he began, but when he noticed the boat going over unusual bumps, unlike before, he realized that 6 to 7 feet of water rose, hiding once-visible cars and stop signs. He was hitting the tops of cars.
"It was all gone," he said.
Despite not knowing how to swim, and being filled with fear, the priest felt called to help and not leave anyone behind.
"Before I started, I prayed to Mary," he said, begging her to be with him. "My heart broke in two. It was too much. The water just kept rising and rising."
Ordained in 2011, the Vietnamese-born priest said he had seen floods before, but had never seen such high water in his life. City officials said at least 70 percent of Harris County was covered in at least 1.5 feet of water.
While bayous and rivers were rising and falling in Victoria and Houston, Harvey's outer bands reached into East Texas, smothering Beaumont and Port Arthur with rain. Shortly offshore and downgraded to a tropical storm, Harvey made a second landfall Aug. 30 with more rain, drenching the already soaked region.
Drainage pumps failed as entire interstates became miles-long extensions of the Gulf of Mexico and the Neches River.
In Beaumont, rising waters cut off the city's water supply. The chancery offices remained closed, Sept. 1 and a nearby hospital evacuated, another on water conservation.
Parishes and schools throughout the Beaumont Diocese saw some damage. At least one parish remained unsafe to visit by the afternoon on Aug. 31. Then, parishes shared plans to host other congregations affected by Harvey.
Beaumont Bishop Curtis J. Guillory dispensed Sunday Mass obligations for the Labor Day weekend for those who could not yet travel.
"Otherwise, all are welcome," a post on the diocesan Facebook page said.
Across the sodden region, Harvey claimed at least 44 lives, leaving tens of thousands displaced into churches, convention and community centers. Some experts estimate total losses from Hurricane Harvey would reach $190 billion, equal to Hurricanes Katrina and Sandy's total combined costs.