WASHINGTON — Brett Kavanaugh took the bench with his new Supreme Court colleagues for the first time Tuesday in a jovial atmosphere that was strikingly at odds with the tension and rancor surrounding his high-court confirmation.

The new justice dived into his new job, asking a handful of questions in the first arguments of the day following a traditional welcome from Chief Justice John Roberts, who wished Kavanaugh “a long and happy career in our common calling.”

Kavanaugh took his seat at the end of the bench to Roberts’ far left, a visible manifestation of a moment that Republicans have dreamed of for decades, with five solidly conservative justices on the court, and Democrats have dreaded.

His path to confirmation was turbulent — opposition to him intensified after Christine Blasey Ford accused him of sexually assaulting her decades ago, when they were teenagers. Kavanaugh denied it.

In court, Kavanaugh asked questions of both sides in arguments over increased prison sentences for repeat offenders. He jumped in with his first question after most of the other justices had spoken.

Questions from Kavanaugh and Justice Neil Gorsuch, President Donald Trump’s two high-court picks, suggested they could vote against the Trump administration and side with a criminal defendant from Florida who is fighting an increase in his sentence from just over six years to possibly more than 15 years.

As Gorsuch did in his first arguments last year, Kavanaugh focused heavily on the importance of following earlier decisions of the court. Both men testified about their respect for Supreme Court precedent, though Gorsuch already has been in the majority to overrule four high-court rulings.

Referring to a 2010 decision known as Curtis Johnson, Kavanaugh asked Justice Department lawyer Frederick Liu what the court should do “if we’re trying to follow Curtis Johnson strictly?”

There were no disruptions in the courtroom, and the justices laughed at one another’s jokes. Justice Sonia Sotomayor even appeared to playfully pinch Gorsuch’s arm as she asked a question about the kind of physical force necessary to have a crime be treated as violent under a federal enhanced sentencing law.

When the session came to an end, Kavanaugh shook hands with his new seatmate, Justice Elena Kagan. They also chatted privately before the arguments began. From time to time, Kavanaugh put on reading glasses to glance at papers in front of him.

Kavanaugh’s wife and two daughters were in seats reserved for justices’ guests, along with retired Justice Anthony Kennedy. Kavanaugh replaced Kennedy on the bench.