As the Italian death toll from the Covid-19 pandemic reached grim new heights last Sunday, Pope Francis broke strict quarantine rules to visit the church of San Marcello in central Rome. The pontiff went to pray for a miracle before a crucifix which the pious believe helped save the city from plague in 1522.

Around him was a country in lockdown and a continental economy in freefall, as the virus spread across Europe, freezing factories, snarling borders, shuttering high streets and confining hundreds of millions of citizens to their homes. Workers, business leaders and investors were seeking deliverance not only from the almighty, but from EU policymakers, who they implored to stop the slump from turning into a lasting depression that could destroy the eurozone.

For a moment last week, it looked like at least some of those prayers had been answered. The European Central Bank stunned global markets on Wednesday night with an audacious plan to expand its asset purchases by a vast €750bn over the next nine months. European bond markets immediately rallied as the scale of the ECB’s intervention became plain, reducing the financing costs of governments from Italy and Greece to Germany and France. “There are no limits to our commitment to the euro,” Christine Lagarde, the ECB president, wrote on Twitter after the plan was unveiled.