Mr Musk said he was “honoured” as he tweeted a photo of himself with the Pontiff and his four teenage sons.
Casually dropping back into his usual style of Twitter posting, Mr Musk wrote: “Honoured to meet @Pontifex yesterday.”
The Tesla CEO also shared an older photo showing him celebrating his 40th birthday in Venice with his then-wife, Talulah Riley.
He tweeted alongside the picture: “Venice, a site of Great Remembrance.”
The break in silence comes as Mr Musk last posted on Twitter on June 21 when he posted a couple of meme images about AI and the price of petrol.
Responding to the image with the head of the Catholic Church, fans were quick to welcome Elon back to the digital world.
One user, Endrina Pavlic, wrote: “Lovely visit…it’s nice to see that your children are with you…it’s a blessing! Tell me your favourite topics that you discussed with @Pontifex?!”
Another, Leica Nelson, wrote: “Good for you! And love that your boys joined you. They look like such a great bunch. Very cool.”
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