Speaking at the newly restored St Anthony's in Colombo, the head of Roman Catholics in Sri Lanka said there were doubts whether the island could pull itself out of crisis after the coordinated suicide bombings on April 21.
At least 54 people were killed at the church, where thousands of people -- including leading politicians -- attended a special trilingual service on Wednesday.
"What we need is a leadership that will work for the country rather than themselves. A leader with a backbone who will not protect the guilty. A leader who is not afraid to punish wrongdoers," said the Archbishop of Colombo, Cardinal Malcolm Ranjith.
"There is some doubt, both here and abroad, whether we have a strong leadership that will deliver us from this crisis," he added.
His remarks came as President Maithripala Sirisena faced serious criticism that he, as minister of defence and Law and Order, failed to act on advance warnings of the Easter attacks.
Prime Minister Ranil Wickremesinghe has publicly apologised for the security lapses that allowed suicide bombers to stage the assaults unchallenged.
Cardinal Ranjith said the Islamist extremists who staged the suicide attacks against three churches and three luxury hotels were misguided youth who will have no place in heaven.
"The innocent victims who died while in church are now angels in heaven. Those who carried out the attacks are in the hell of hells," Ranjith said.
St Anthony's -- which dates back to 1740 -- is venerated by non-Catholics too and as its restoration was nearing completion, India's Prime Minister Narendra Modi made an unannounced visit on Sunday and paid tribute to all the victims.
"I am confident Sri Lanka will rise again," Modi said on Twitter where he posted photos of himself at the church.
"Cowardly acts of terror cannot defeat the spirit of Sri Lanka. India stands in solidarity with the people of Sri Lanka."
Wickremesinghe said he had discussed with Modi ways to combat militant attacks and counter religious extremism.
Sri Lanka has been under a state of emergency since the assaults, giving the police and security forces sweeping powers to arrest and detain suspects for long periods.
The authorities have said they have killed or arrested all those responsible for the Easter Sunday attacks that were blamed on a local jihadi group, the National Thowheeth Jama'ath (NTJ) and claimed by the Islamic State.