Take a line you want to hide, change its configation tag to 'myHidden' or something. Configure the properties for 'myHidden' so that the foreground and background colors are the same as the background color for the Text Widget.

use strict ;
use Tk ;
use Tk::Text ;

my($mw) = new MainWindow ;

my($txt) = $mw->Scrolled('Text', 
                         -background => 'white', 
                         -foreground => 'black')->pack(-expand => 1, -
+fill => 'both') ;

$txt->tagConfigure('myHidden', -foreground => 'white', -background => 
+'white') ;

$txt->insert('end', "line1\n", 'default') ;
$txt->insert('end', "line2\n", 'myHidden') ;
$txt->insert('end', "line3 (what happened to line2??)\n", 'default') ;

MainLoop ;
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