"Putting on a robe reminds us that it's time to lose our egos and open our minds," Gorsuch told members of the Senate Judiciary Committee.
"When I put on the robe, I am also reminded that under our Constitution, it is for this body, the people's representatives, to make new laws, for the executive to ensure those laws are faithfully enforced and for neutral and independent judges to apply the law in the people's disputes," he said.
He went on, "If judges were just secret legislators, declaring not what the law is but what they would like it to be, the very idea of a government by the people and for the people would be at risk. And those who came to court would live in fear, never sure exactly what governs them except the judges' will."
Calling judgeship a "lonely and hard job," Gorsuch touched on some of the concerns that Democrats expressed in their remarks leading up to his testimony.
"These days we sometimes hear judges cynically described as politicians in robes, seeking to enforce their own politics rather than striving to apply the law impartially," he said. "But I just don't think that's what a life in the law is about."
Gorsuch also paid homage to the man he is seeking to replace on the high court, Antonin Scalia, and called him a mentor.
The hearing began with high praise from Republican senators on the committee, who hailed Gorsuch as an "exceptional" nominee. Democrats, however, expressed concern over his conservative principles.
In his opening statement, Sen. Chuck Grassley, the chairman of the Senate Judiciary Committee, praised Gorsuch's record as a federal judge.
"Fortunately for every American, we have before us today a nominee whose body of professional work is defined by an unfailing commitment to these principles. His grasp on the separation of powers — including judicial independence — enlivens his body of work," Grassley said.
He continued, "The nominee before us understands that any judge worth his salt will 'regularly issue judgments with which they disagree as a matter of policy — all because they think that's what the law fairly demands.'"
Sen. Dick Durbin, D-Ill., underscored the need for an objective Supreme Court judge in light of the Trump presidency.
"You are going to have your hands full with this president," Durbin said. "He will keep you busy. It is incumbent on any nominee to demonstrate that he or she will serve as an independent check or balance on the presidency."
Sen. Lindsey Graham, R-S.C., said in his remarks, "Donald Trump deserves to be congratulated for listening to a lot of people and coming up with what I think is the best choice available in terms of nominating someone who will keep the conservative philosophy alive and well in the court."
Sen. Dianne Feinstein, the committee's ranking member, addressed issues of relevance to Democrats in her prepared remarks — reproductive rights, voting rights, campaign finance, the environment and gun control.
"We're here today under very unusual circumstances," she said, pointing out that nearly a year ago, then-President Obama nominated Merrick Garland as the next Supreme Court justice. Garland was never granted a confirmation hearing, after strong opposition from Republicans.
"I just want to say I'm deeply disappointed that it's under these circumstances that we begin our hearing," she added.
She stressed the role of the Supreme Court in upholding landmark decisions and protecting the constitutional rights of all Americans, including women, people of color, other minorities and the poor.
Sen. Mazie Hirono, D-Hawaii, told Gorsuch that she had "not seen that the rights of minorities are a priority for you. In fact, a pattern jumps out at me. You rarely seem to find in favor of the little guy."
She continued, "The Supreme Court shapes our society ... Will America be a land of exclusivity for the few or the land of opportunity for the many? Will we be a compassionate and tolerant America that embraced my mother, my brothers and me? ... You consistently choose corporations and powerful interests over people."
Gorsuch, 49, is a judge on the 10th Circuit Court of Appeals in Denver. He was nominated by President George W. Bush in 2006 and confirmed by the Senate in a voice vote. He clerked for Judge David B. Sentelle on the United States Court of Appeals for the D.C. Circuit and then for Justices Byron White and Anthony Kennedy on the Supreme Court. He attended Harvard Law and has a Ph.D. from Oxford, where he was a Marshall scholar.
Like Scalia — who died at the age of 79 in February 2016 — Gorsuch is a textualist and an originalist. And his views, background and legal writings will be publicly scrutinized over the course of the weeklong proceedings.
"I am concerned when I hear that Judge Gorsuch is an originalist and a strict textualist," Feinstein said.
In legal circles, Gorsuch is considered a gifted writer. In his book, "The Future of Assisted Suicide and Euthanasia," which examines the legal and ethical issues surrounding assisted suicide, he concludes that any form of euthanasia should not be legalized.
Law professor Carl Tobis said he believes the questioning at Gorsuch's hearings will be "respectful" but "rigorous."
Tobias added that he expects "GOP members to strongly support Gorsuch and to ask questions that make him appear within the mainstream" while Democrats "will ask about areas, issues and views where he might appear to be outside the mainstream. One key area is judicial deference to the executive generally and this president specifically, deference to administration."
When it comes to religious liberties and access to contraception, Gorsuch is a defender of the First Amendment's free exercise clause, which reads, "Congress shall make no law respecting an establishment of religion or prohibiting the free exercise thereof."
He sided with Christian employers and religious organizations in the Burwell v. Hobby Lobby and Little Sisters of the Poor cases, in which the plaintiffs argued for an exemption from the contraception mandate in Obama's signature health care legislation, the Affordable Care Act, citing their religious beliefs.
In the Hobby Lobby case, Gorsuch wrote, "The ACA's mandate requires them to violate their religious faith by forcing them to lend an impermissible degree of assistance to conduct their religion teaches to be gravely wrong."
When it comes to criminal procedure, he dissented in the United States v. Carlos case, arguing that police officers violated the Fourth Amendment when they entered a home that had a "no trespassing" sign posted.
In a press conference last week, Senate Minority Leader Chuck Schumer of New York cautioned that Gorsuch has important questions to answer about some of his opinions, most notably "his decisions he wrote that favored the powerful over the powerless."
Schumer last week suggested that he would not support the confirmation of Gorsuch and urged his Senate Democratic colleagues to do the same.
Gorsuch supporter Leonard Leo of the Federalist Society told ABC News he is confident that "Gorsuch will be confirmed."
The hearings are expected to conclude by the end of the week.