• Christians gather at a church in Lahore. Pakistan's three million strong Christian community fears persecution. Picture: Getty
Asia Bibi, 45, was arrested last year after being accused of defaming the Prophet Muhammad, the founder of Islam.
The mother-of-five denied the charges but was sentenced to death by a court on Monday, provoking outrage among Christian groups and human rights advocates. They say Pakistan's strict blasphemy laws are being used to discriminate against religious minorities and should be repealed.
Her supporters say Mrs Bibi will now appeal against the sentence handed down by a local court in the town of Sheikhupura, near Lahore.
Ashiq Masih, her husband, said the family was in a state of shock and believed the judge had been pressured into finding his wife guilty.
"It is an unjust decision," he said. "I can't believe it."
He added that he had not yet had the heart to break the news to his youngest children.
"I haven't told two of my younger daughters about the court's decision," he said.
"They asked me many times about their mother but I can't get the courage to tell them that the judge has sentenced their mother to capital punishment for a crime that she never committed."
The court heard she had been working as a farmhand in fields with other women, when she was asked to fetch drinking water.
Some of the other women - all Muslims - refused to drink the water, sparking a row. They said, as it had been brought by a Christian, it was "unclean", Mrs Bibi said in evidence.
The incident was forgotten until a few days later when Mrs Bibi said she was set upon by a baying mob. The police were called and took her to a police station for her own safety.
Shahzad Kamran, of the Sharing Life Ministry Pakistan, said: "The police were under pressure from this Muslim mob, including clerics, asking for Asia to be killed because she had spoken ill of the Prophet Muhammad.
"So after the police saved her life they then registered a blasphemy case against her."
He added that she had been held in isolation for more than a year before being sentenced to death on Monday.
"The trial was clear," he said.
"She was innocent and did not say those words."
Although no-one has ever been executed under Pakistan's blasphemy laws - most are freed on appeal - as many as ten people are thought to have been murdered while on trial.However, human rights groups believe the blasphemy law is most often used to discriminate against religious minorities, such as the estimated three million Christians, in a country of 126 million people.
In July, two Christians charged with blasphemy were shot dead outside a court in Faisalabad.
A report by the US Commission on International Religious Freedom last year concluded: "Although there have been occasional acquittals on blasphemy charges, in virtually all cases those acquitted have been forced into hiding or even exile, out of fear of attacks by religiously-motivated extremists."
Ali Hasan Dayan, of Human Rights Watch, said the blasphemy laws were out of step with rights guaranteed under Pakistan's constitution and should be repealed.
"It's an obscene law," he said. "Essentially the blasphemy law is used as a tool of persecution and to settle other scores that are nothing to do with religion.
"It makes religious minorities particularly vulnerable because it's often used against them."
SECULAR HOMELAND OR ISLAMIC STATE?
Pakistan has a complex relationship with religion.
Although founded as a secular homeland for India's Muslims, in the 1970s and 1980s, under political leaders such as Zia ul-Haq and Zulfikar Ali Bhutto, it followed a programme of Islamisation. This led to bans on alcohol and the introduction of other measures to win support from hard-line religious parties.
General Zia also introduced Shariah law as a basis for lawmaking, a move reinforced by Nawaz Sharif in 1991.
Coerced conversions to Islam from Christianity remain a major source of concern for Pakistani Christians, who have faced threats, harassment and intimidation from Islamic extremists. Often, converts to Christianity from Islam face the death penalty.
Christians, with all non-Muslims, are also subject to constitutional discrimination. They are barred from becoming president or prime minister and from being judges in the Federal Shariat Court, which can overturn any "unIslamic" legislation.