In their first interview as a couple since assuming the roles of president and first lady, Joe and Jill Biden spoke with People magazine about supporting each other over 43 years of marriage.

She has a backbone like a ramrod, the president said in the interview, which was published on Wednesday. Everybody says marriage is 50/50. Well, sometimes you have to be 70/30. Thank God that when Im really down, she steps in, and when shes really down, Im able to step in. Weve been really supportive of one another.

He added that he was glad his wife had kept working as a college professor over the decades, stressing that in order to keep a marriage strong, it was important for both parties to have their separate passions and goals.

Jill Biden , who still teaches English composition at Northern Virginia Community College and has a doctorate in education, is the first first lady with a paying job outside the White House .

Its important that she has the things that she cares a great deal about, her independence, the president said. And yet we share each others dreams.

Jill Biden said that the couple had endured much pain together over the years, a likely reference to the loss of her stepson Beau Biden, who died from a brain tumor in 2015 at the age of 46.

Beau was the eldest child of Joe Biden and his first wife, Neilia Hunter Biden, who died in a car crash in 1972 with the couples one-year-old daughter, Naomi.

All that weve been through together the highs, the lows and certainly tragedy and loss theres that quote that says sometimes you become stronger in the fractured places, she said. Thats what we try to achieve.

The president, when asked if he would be able to perform his role without the support of his wife, stressed that we each could do our jobs, but not as well as we do them, adding that she was the glue that held it together.

Its not that we dont fight and argue sometimes, he said. Im just lucky.

Well, after 43 years of marriage theres really not that much more to fight about, the first lady added.

The couple, who married on June 17, 1977, also touched on Joe Bidens Catholic faith which the president equated to meditation and the surreal experience of re-entering the White House after having spent so much time in it when he served as vice president in Barack Obama s administration.

Read the full interview here .