"This is one of the characteristics of the entire pontificate, which social media helps to emphasize," he said.
Papal involvement in social media began with Pope Benedict XVI.
"Benedict XVI said that life on the internet is an apostolic activity," Msgr. Vigano said. "We must live in these spaces with responsibility, as the internet spaces are neither good nor bad… they are simply different than the usual spaces for traditional communication."
He criticized the claim that social media is not important, saying that people who make this argument are unusually older and have "lived in an era without social media."
"But we should overcome this thought," he emphasized.
The monsignor noted areas of social media where evangelization can take place.
"There are often groups of young people who attend catechesis and then continue their dialogue on the social networks. And there are people who find in social networks the motivation to have a personal meeting in catechesis."
He stressed that social networks offer the opportunity to "enlarge our communities, expanding the possibility to reach out to people."
Msgr. Vigano noted that social media audiences can skew young. "Especially Instagram. Ninety percent of Instagram users are under 30," he observed.
This provides a very useful channel for the message of the Pope, the Gospel and the Church, he continued.
For Instagram, the message is in an image that "speaks emotionally." For Twitter, which provides a 140-character limit on text messages, the message is "very short."
"But this does not make the message less valuable," Msgr. Vigano stressed.
He compared the brevity of a Tweet to the recommendations of the Catholic tradition that praise "even very short moments of prayer."