Pope Francis has finally joined the Instagram on March 19, with about 1.5 million likes already.

His first post was not a selfie, but himself praying with caption "pray for me" written in nine languages.

His other posts have him praying at the cross, and a video where the Pope delivers a message of mercy and tenderness.

Pope Francis had met with the CEO of Instagram, Kevin Systrom, last month.

Vatican's first prefect of the newly-established Secretariat for Communications said that the pontiff's Instagram will "help recount the papacy through images, to enable all those who wish to accompany and know more about Pope Francis's pontificate to encounter his gestures of tenderness and mercy... We will choose photographs from the photographic service of L'Osservatore Romano ... In this way we can show those aspects of closeness and inclusion that Pope Francis lives every day."

Instagram was bought by Mark Zuckerberg, founder and CEO of Facebook in 2012.

Zuckerberg welcomed the Pope by writing a message for him on his personal Facebook page.

"Welcome to Instagram, Pope Francis! No matter what faith you practice, we can all be inspired by Pope Francis's humility and compassion," he wrote. "I'm looking forward to following the Pope - and watching him continue sharing his message of mercy, equality and justice with the world."

The pope posted his first message on Twitter in March 2013 as @pontifex, which now has nine different versions in English, Arabic, French, Spanish, Polish, Latin, German, Portuguese and Italian, and some 27 million followers.