John F Kennedy Quote?

Presidential Proclamation 3560 : Thanksgiving Day.

November 5, 1963. (17 days before his assassination).

It's part of the President's annual proclamation of a National Day of Thanksgiving.

The entire paragraph from which the quote comes reads as follows:

Yet, as our power has grown, so has our peril. Today we give our thanks, most of all, for the ideals of honor and faith we inherit from our forefathers - for the decency of purpose, steadfastness of resolve and strength of will, for the courage and the humility, which they possessed and which we must seek every day to emulate. As we express our gratitude, we must never forget that the highest appreciation is not to utter words but to live by them