When President Trump recently met Pope Francis, the pope gave him a copy of his prophetic message to the world: Laudato Si’: On Care for Our Common Home. In this encyclical, penned two years ago, the pope described climate change as a real and substantiated issue, with human causes. He called upon the world to work toward a solution, and to do so before the current crisis becomes a full-blown, irreversible catastrophe for the planet. Now, in what can only be considered a not-so-subtle message, the pope has given this encyclical to the president—supposedly the “leader of the free world”—a man who has not only stated that he does not believe in climate change, but who has also chosen many others sharing that belief to hold important decision-making positions in his administration.

I am stunned by the contrast between these two men—the pope and the president—and all the more so after seeing reports about their recent meeting. Pope Francis’s very being espouses love and mercy. He is humble, he is modest, he values simplicity. In his compassion, we see him greeting Trump, a man who seems determined to use his power to undermine what is good and just in the world.

While the pope as pontifex maximus is the great bridge builder between cultures, religions, and people, Trump’s signature cause is the building of walls. The wall between Mexico and this country is one physical example, but the walls of divisiveness take many forms. Even in his short time in office, Trump has engaged in a relentless campaign to silence the free press and to fracture the functioning of a viable democracy. He has distanced this country from our allies. By the time you read these words, he may have withdrawn the U.S. from the Paris Agreement on climate change. We hear daily of his efforts to extinguish social initiatives and to take health care and other vital services from those who need them most, while at the same time adding to the coffers of the wealthy. And all this from the man who pledged to drain the swamp.

We have to wonder: will the pope’s not-so-subtle message have an impact on the president? Time will tell. In the meanwhile, now is the time to push back against regressive changes. We must respond in concert with the invitation of Pope Francis—by acting as people of mercy; by protecting the beauty of creation, as manifest in every rose, child, river, and tree; by remembering the goodness of life and invoking the gracious presence of an ever-loving God; and by actively resisting all agendas that threaten the future of the world as we know it.