The archbishop of Boston received a standing ovation at St. Theresa of Avila Parish April 1 at the beginning of his first public Mass since being elevated to the College of Cardinals last month.

“It’s a great joy to be here,” Cardinal Sean O’Malley told the packed church.

According to a report in Boston’s diocesan newspaper, The Pilot, the new cardinal began his homily by speaking about the universality of the Church and the role of the Pope, who unites Catholics throughout the world.

He explained that the red robes of a cardinal, which he wore under his purple vestments, is a reminder that the Catholic Church is a Church of martyrs. “We must be ready to suffer to bear witness to our faith,” he said.

His purple Lenten vestments, with gold, red and green embroidery down the center, were Pope John Paul II’s. They were a gift from Pope Benedict XVI after he was elevated to cardinal. Cardinal O’Malley felt it appropriate to don the vestments of the late pope as the one-year anniversary of his death would be commemorated the following day.

Cardinal O’Malley said Lent should be less about sticking to our promises to give up sweets or cigarettes and more about obeying and getting to know Christ.

“Lent should mean turning our backs on everything that separates us from Christ and each other,” he said. “Lent is about dying to the selfishness of sin and individualism and being able to experience the joy of Christ.”

He reminded the congregants not to be afraid to follow Christ. “During Lent, look to Jesus lifted up on the cross,” he said. “If we really see the cross, we see love, obedience, hope — and if we really see Jesus, we see that He is always watching us with love — love that gives us the courage to stop following Him at a safe distance and follow Him up close.”

Cardinal O’Malley also celebrated Mass at St. Catherine of Siena in Norwood April 9 and is scheduled to celebrate at St. Mary of the Assumption in Lawrence April 16 in Spanish.