A congregation in Dublin have forgiven a man who robbed them at gunpoint on Sunday.

A man wearing a balaclava and wielding a sawn-off shotgun entered the Compassion Centre, a Christian outreach centre in Ballymun, through the back door at around noon on December 6. He demanded the congregation of about 40 people lie on the ground and hand over bags, purses and mobile phones before fleeing in a stolen blue Fiat Panda.

"He put a gun to one of the members' heads, gave him a bag and told him to collect the money and phones. He did that and then he fled," senior pastor John Eniola said.

"It was frightening but we all stayed calm and did not struggle...Thankfully nobody was hurt. There was no fire."

Immediately after the robbery, the congregation stood together and prayed for the gunman. "We just gathered in prayer, prayed for each other and prayed for him mostly," said Dan Tab, a missionary from the church.

"We look forward to seeing him in church some day, that was really what our prayer was, we prayed quite a bit about that."

Speaking to Christian Today, Eniola echoed Tab's sentiment.

"Of course [we prayed], that is what Jesus would do if he was here," he said.

"We believe that we are different, we have the mind and heart of Christ, and we believe also that he [the gunman] did it out of ignorance. If he knew what he was doing, he wouldn't do it.

"We are all saved by grace, which is why we decided to pray for him and show mercy. We asked the Lord to forgive him and save his soul, and I believe that one Sunday he will return back to church and share his testimony: 'I robbed this church one day, and now I'm preaching in it.'"

Eniola said that he sees yesterday's incident as an opportunity to share about Christ's forgiveness. The Lord is already bringing good things out of a horrible situation, he said.

"We are more popular than the President at the moment!" he laughed. "Every TV station, every news station is interviewing us, we're on the front pages of all the papers and we're on the radio, it's been wonderful. I keep telling of the forgiveness of Christ and of how we prayed for the Lord to forgive him and save his soul. It's great to show the mercy of Christ in a difficult time on national television.

"People keep asking me if we'll be back next Sunday, and I say 'My God, we'll be back on Wednesday for Bible study!'" he added. "We were shaken, but not broken."

The Compassion Centre was set up in 2009, and provides help for the homeless, drug addicts, and people with mental health problems. It planted the church in Ballymun, an area known for violence, in August last year.

"Ballymun is a very notorious place for gangs, robbery and criminalities, but someone has to come here for Jesus," Eniola said.

"We are the only evangelical church in this area. Most churches don't want to come here because they know what it is like. But we are encouraged, we see ourseves as missionaries, and we have to stand with Jesus.

"This is a very bad area, but we believe God can heal it."

Local police are investigating the incident and have appealed for information.