These definitions are in Webster’s New Collegiate Dictionary 1980:

tolerance n…. 3a: sympathy or indulgence for beliefs or practices differing from or conflicting with one’s own.  b: the act of allowing something.

tolerant adj… 1: marked by forbearance or endurance.

tolerate vt [L toleratus, pp of tolerare to endure, put up with …] … 2: to suffer to be or to be done without prohibition, hindrance, or contradiction.

To tolerate something is to put up with it. Tolerance is the suffering of something ; the permitting of it to exist. If you tolerate something it does not mean that you like it, admire it, or want it to exist; only that you will let it be. You might possibly have ‘sympathy for’ it, but it is not what you yourself believe or hold highest in your esteem.

Tolerance is a virtue practiced by the upholders of freedom. A belief in freedom entails it. Just as you yourself must be free to think, say, and do whatever you please (within the legal restraints you choose to obey), so your fellow man is free in precisely the same way. You may positively hate his beliefs, his actions, his taste, his manner, his appearance, his opinions, but as long as none of these impede your own freedom, you must necessarily, in the logic of your principles, tolerate them.

The one thing that the tolerant cannot logically tolerate is intolerance.

To tolerate intolerance is to condone it. To condone it is to deny tolerance. Only by not tolerating it can you remain tolerant. It is a simple case of two negatives making a positive – do not tolerate intolerance, and you are tolerant; tolerate it, and you have lost your virtue.

We atheists suffer others to believe what they will. We do not want to stop them believing what they do, or change their minds, or punish them in any way for believing something that we do not. We do not want them to be interfered with in any way unless they fail to reciprocate our live-and-let-live forbearance and themselves interfere with us or others who differ from them.

Any belief, political or religious, that disallows or punishes dissent is the enemy of tolerance and should not be tolerated.

A policy that does not permit sane adults to do what they will provided they harm no one else should be abandoned.

A religion that punishes apostasy should not be tolerated in a free society.

An ideology that is against freedom is intolerable.