LONDON (AP) — The Twitter account of Britain’s royal family has featured a tribute Queen Elizabeth II gave to Prince Philip for the couple’s 50th wedding anniversary.

An excerpt from a speech the queen made in 1997 was posted Saturday, the day after Philip died at age 99.

“He has, quite simply, been my strength and stay all these years, and I, and his whole family, and this and many other countries, owe him a debt greater than he would ever claim, or we shall ever know,” Elizabeth said of her husband in the anniversary speech.

Philip also had words of gratitude for his wife and monarch at the time.

“I think the main lesson that we have learnt is that tolerance is the one essential ingredient of any happy marriage,” he said. “You can take it from me that the queen has the quality of tolerance in abundance.”

A portrait of the couple taken by photographer Anne Leibovitz and first released in 2016 on Philip’s 95th birthday accompanied Saturday’s Twitter post.