Complement can mean complete and compline means to complete the day. It is the last prayer of the day or night prayer. I am thinking of compline because I am a fan of the PBS program “Call the Midwife.” It is based on the memoires of Jennifer Worth who worked as a Nurse-Midwife in the 1950s at Nonnatus House, a residence of Anglican nuns who were also Nurse-Midwives. The nuns and lay midwives provided maternity and public health care to a poor London area after WWII.
The compline is mentioned by the nuns in the show, and they are sometimes depicted in a compline service in the church at the end of the day. They stand together and chant the prayers.
I admire the dedication of all nuns. When I was little I thought of nuns as so stern and perfect. They were without fault. They would not allow themselves to commit any sins. I did not see their humanity.
One of first Nursing positions I had, as a young woman, was at a Catholic hospital in San Francisco. I met a nun who visited our unit. I sat with her in the cafeteria one day and she told me of a recent experience she had when she visited a patient in a Nursing Home. She said the person had loss the use of their hands and expressed their despair to her. The Sister said she had been depressed by it. I had an epiphany then. Nuns can get depressed too. They can have times when they are not strong just like everyone else.
Yet, they keep rededicating themselves to service.