That ugly treason of mistrust. [ William Shakespeare, The Merchant of Venice ]

Hypocrisy is permanent treason.

Ingratitude is treason to mankind. [ Thomson ]

Treason seldom dwells with courage. [ Sir Walter Scott ]

Whoever is suspicious incites treason. [ Voltaire ]

O comfort-killing Night, image of hell!
Dim register and notary of shame!
Black stage for tragedies and murders fell!
Vast, sin-concealing chaos! nurse of blame!
Blind, muffled bawd! dark harbor for defame!
Grim cave of death! whispering conspirator,
With close-tongued treason and the ravisher! [ William Shakespeare ]

Treason doth never prosper; what's the reason?
Why if it prosper, none dare call it treason. [ Sir J. Harrington ]

Treason has done his worst; nor steel, nor poison,
Malice domestic, foreign levy, nothing
Can touch him further. [ William Shakespeare, Macbeth ]

Trust not the treason of those smiling looks.
Until ye have their guileful trains well tried;
For they are like but unto golden hooks.
That from the foolish fish their baits do hide:
So she with flattering smiles weak hearts doth guide
Unto her love, and tempt to their decay;
Whom, being caught, she kills with cruel pride,
And feeds at pleasure on the wretched prey. [ Spenser ]

There is no traitor like him whose domestic treason plants the poniard within the breast which trusted to his truth. [ Byron ]

Capable of all kinds of devotion, and of all kinds of treason, raised to the second power, woman is at once the delight and the terror of man. [ Amiel ]