Lyndon Johnson actually said...

This is a very happy and historic occasion for all who love the great American outdoors, and that, needless to say, includes me.

My regret at your leaving is tempered by satisfaction in the knowledge that you intend to continue your service to your country.

No single Congress in my memory has done so much to keep America as a good and wholesome and beautiful place to live.

It is with regret that I have received your resignation.