For Ivanka Trump and her husband, Jared Kushner, celebrating the presidential inauguration by attending the gatherings on Friday night posed an obstacle to their Orthodox Jewish observance of the Sabbath.

Ms. Trump, President Trump’s older daughter, and Mr. Kushner got special permission to break from strict religious laws that prohibit them from using technology or mechanized devices, such as cars, during the Sabbath, which begins on Friday evening.

A Jewish person who was briefed on the matter but not authorized to speak publicly about it said on Friday night that they were given an exemption under the principle in Jewish law of pikuach nefesh, which suggests preserving the safety of a specific person over any religious consideration.

In the case of Mr. Kushner and Ms. Trump, that would have meant being outside security escorts once the Sabbath had started.