"There is a motto which has been borne by many of my ancestors — a noble motto, "I serve". Those words were an inspiration to many bygone heirs to the Throne when they made their knightly dedication as they came to manhood. I cannot do quite as they did. But through the inventions of science I can do what was not possible for any of them. I can make my solemn act of dedication with a whole Empire listening. I should like to make that dedication now. It is very simple. I declare before you all, that my whole life, whether it be long or short, shall be devoted to your service and to the service of our great imperial family, to which we all belong. But I shall not have the strength to carry out this resolution alone, unless you join in it with me as I now invite you to do. I know that your support will be unfailingly given. God help me to make good my vow and God bless all of you, who are willing to share with it."
January 1, 1970
https://en.wikiquote.org/wiki/Elizabeth_II