"My initial response is that I was angry. I was angry. How could somebody do this?" he recalled.
That anger quickly turned into action.
Rather than watching events unfold from afar, Messick answered a call for chaplains to assist at the World Trade Center disaster site in New York City.
"I just looked around and saw the destruction and then the smells, the sights, the heat," Messick recalled. "And what came to mind was something from the Bible. I thought of the 23rd Psalm: 'Yea, though I walk through the valley of the shadow of death.'"
So many lives lost, so much destruction, pain, tears, and for this pastor who always has the right thing to say, September 11th momentarily silenced him; the images were unforgettable.
"I looked down, and I saw a woman's red shoe and a man's brown shoe, and I thought to myself, 'I wonder what happened to them?'" he said. "It started to make it real."
By the time Messick arrived at ground zero, rescue efforts had largely become a recovery mission.
Once he arrived, it was no longer a rescue mission but a recovery. He knew his job was what he called, "ministry of presence." Just be there, pray with them, listen, and get first responders, some of whom hadn't, just to talk.
"They said this to me, and this made a big difference," Messick said. "They said, 'You need to know how we view this place. This is holy ground, and for you to be here and stand with us helps give meaning to what we are doing.'"
Messick spent 30 days traveling to ground zero and said the experience taught him lessons about perseverance, endurance and faith during life's most difficult moments.
He believes the experience not only helped the first responders he served but also changed him personally.
"As far as my sermons, I'd have to ask the church if my sermons got better or not," he said with a laugh. "But I know I got bolder about talking about the issues of life because I saw people in the very worst situations."
Today, Messick continues his ministry in Collingdale, carrying forward the lessons he learned after 9/11.
One message, he said, remains as important now as it was then: sometimes, there is no answer to why, but there is always hope.
"Not just 9/11, but dealing with issues of life, loss of loved ones," Messick said. "There is purpose for your life. If you are here and you are still breathing, there is purpose for your life."