ROME — Perhaps the timing was purely coincidental. But a day after he was credited with helping to broker the historic diplomatic breakthrough between Cuba and the United States, Pope Francis began his Thursday morning by greeting a new crop of envoys to the Vatican, and offering some advice.

“The work of an ambassador lies in small steps, small things, but they always end up making peace, bringing closer the hearts of people, sowing brotherhood among people,” he said. “This is your job, but with little things, tiny things.”

Yet if the Vatican has long practiced a methodical, discreet brand of diplomacy, what has changed under Francis — or has been restored — is a vision of diplomatic boldness, a willingness to take risks and insert the Vatican into diplomatic disputes, especially where it can act as an independent broker.

Even as the Vatican has spent decades building trust in Cuba, and working steadily to break down the impasse with the United States, it was Francis who took the fateful risks — writing secret letters to President Obama and President Raúl Castro of Cuba, and then offering the Vatican for a secret and critical meeting between both sides in October.