Both marriage and death ought to be welcome: The one promises happiness, doubtless the other assures it.
— Mark Twain

assurance is two-thirds of success.
Scottish Proverbs assurance quote

Perhaps nature is our best assurance of immortality.
— Eleanor Roosevelt

Whenever you are angry, be assured that it is not only a present evil, but that you have increased a habit.
— Epictetus

It may be said with a degree of assurance that not everything that meets the eye is as it appears.
— assurance quotation by Rod Serling