In his concurring opinion, he noted that "all citizens are equally American, no matter what God they worship or if they worship no god at all."
He argued that, even though some forms of public prayer, like those at presidential inaugurations, were part of long-established traditions and not, therefore, a violation of the constitutional separation of church and state, "we cannot resolve this case by discounting the sense of anguish and outrage plaintiffs and some other Americans feel at listening to a government-sponsored religious prayer."
Some commentators have called this recognition of atheistic objections "troubling." Yet others have acknowledged the common thread between the two opinions in Newdow and Priests for Life. A crucial part of Kavanaugh's approach to religious liberty appears to be the legitimacy of individual conscience in front of a court.
This was also a key issue in the Masterpiece Cakeshop case, where the disregard of Colorado authorities for Christian beliefs figured heavily in the Supreme Court's decision.
Looking ahead, the Supreme Court seems likely to hear more such cases in the future.
For example, despite new rules from the Department of Health and Human Services meant to protect religious non-profit organizations and broaden religious exemptions, the Little Sisters of the Poor are back in court over their refusal to provide abortifacient drugs as part of their health care plan.
Pennsylvania Attorney General Josh Shapiro filed suit against the federal government in October of last year, seeking to end the religious exemption for the Little Sisters of the Poor. A similar suit was also filed by the state of California.
Should those or similar cases progress, the importance of private conscience could again prove crucial in the Supreme Court's reasoning, and Kavanaugh could well prove to be the deciding vote.