Inauguration Day began with a private Mass of Thanksgiving held at St. Matthew's Cathedral in Washington, for the Biden family and congressional leadership. The inauguration itself started with an invocation by Jesuit Father Leo O'Donovan, and the inauguration was layered with Catholic touches that reflected President Joe Biden himself.

President Biden is a Catholic, and not just in a cultural way or a Christmas-and-Easter-only way. He's a Sunday and sometimes daily Massgoer kind of Catholic. Archbishop José H. Gomez, president of the U.S. Conference of Catholic Bishops, acknowledged this in his extraordinary 1,250-word statement following the inauguration.

"It will be refreshing to engage with a president who clearly understands, in a deep and personal way, the importance of religious faith and institutions," Archbishop Gomez said.

"Mr. Biden's piety and personal story, his moving witness to how his faith has brought him solace in times of darkness and tragedy, his longstanding commitment to the Gospel's priority for the poor -- all of this I find hopeful and inspiring."

There is a host of issues on which President Biden and Church leaders all the way up to the Vatican agree. Reinforcing Archbishop Gomez's claim that "our priorities are never partisan," in the 24 hours after the inauguration, the U.S. bishops' conference issued four statements endorsing initial actions by the new president. There is the potential for common ground on everything from the death penalty and health care to refugees, poverty relief and fighting racism.

But Archbishop Gomez sees reason to be frustrated with President Biden as well. Over his long political career, President Biden has come to differ with Church leaders in terms of public policy on such issues as "abortion, contraception, marriage and gender." In fact, on Jan. 22, the new administration affirmed its desire to preserve access to abortion.

For President Biden's Catholic critics, these exceptions to the teachings of the faith he professes are maddening. Some will simply not vote for him, but others demand that he be denied Communion because of his contrarian stances, calls that his current bishop, Cardinal Wilton D. Gregory, will ignore.

Archbishop Gomez is cleareyed about where the Church differs with President Biden as well as where it agrees. He seemed to be addressing part of his statement to the president's critics as well as to the president: "Real reconciliation requires patient listening to those who disagree with us and a willingness to forgive and move beyond desires for reprisal," he concluded. "We are all under the watchful eye of God, who alone knows and can judge the intentions of our hearts."

Archbishop Gomez has been criticized for the timing of his unusual and lengthy statement, coming as it did on Inauguration Day. There are clearly those who feel he went too far, and those who feel he did not go far enough.

I hope that President Biden takes the archbishop at his word: "I look forward to working with President Biden and his administration. ... As with every administration, there will be areas where we agree and work closely together and areas where we will have principled disagreement and strong opposition." As an experienced politician, President Biden would expect nothing less.

I hope Catholics take to heart the archbishop's words as well: That instead of condemnation and vitriol, we "bless those who oppose us, and ... treat others with the same compassion that we want for ourselves."

The battle on behalf of the unborn has been going on for more than half a century in our country. It did not end with the last presidency. It will not end with this presidency. It will not end because it is part of the great weave of Catholic social teaching that is, in the words of Archbishop Gomez, "guided by Christ's great commandment to love and stand in solidary with ... the most vulnerable."

Let's accomplish what we can and fight for what we must. The day is long, and there is much to do.

- Greg Erlandson is director and editor-in-chief of Catholic News Service.