Pope Benedict XVI he sent his first tweet from his new account, a move seen as part of the Catholic Church's attempt to attract a new audience of believers through social media.
In perhaps the most drawn out Twitter launch ever, the 85-year-old Benedict pushed the button on a tablet brought to him at the end of his general audience of Wednesday.
"Dear friends, I am pleased to get in touch with you through Twitter.Thank you for your generous response. I bless all of you from my heart," his inaugural tweet read.
At around the same time the message was sent, the number of followers of his twitter account @Pontifex, hit the one million mark of followers.
Later in the day Benedict was to respond to a few questions about faith sent to him from around the world.
The first papal tweet has been the subject of intense curiosity for months.
Benedict actually sent his very first tweet over a year ago, using a generic Vatican account to launch the Holy See's news information portal.
Someone in his name tweeted daily during Lent, part of the Vatican's efforts to increase the church presence in social media.
A personal Twitter account for the 85-year-old Benedict has been the subject of speculation ever since the Vatican's senior communications official said in February the idea was gaining traction.
The leader of the world's 1.2 billion or so Roman Catholics is expected to sign off, rather than write, each individual tweet himself.
Vatican officials have acknowledged the pope will not actually type the messages and that someone in the Vatican's secretariat of state will write them on his behalf.
But they have insisted that the words will be his alone, culled from his speeches, homilies or catechism lessons.
The Catholic Church already uses several social media platforms, including text messages and YouTube, to communicate with young people, while having its own newspaper, television service a dedicated YouTube channel and an Internet news portal.