Name:     state
       Class:    State
       Switch:   -state
           Specifies one of two states for the text:  normal or disabl
+ed.  If
           the text is disabled then characters may not be inserted or
+ deleted
           and no insertion cursor will be displayed, even if the inpu
+t focus
           is in the widget.
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While this may seem inconsistent when compared with the behavior of other widget classes, I've always assumed there was a good reason for it. If you want a Text widget that can't be modified, but that doesn't require toggling -state, you can always use Tk::ROText, which replaces the bindings that are normally used to modify the text with noops.