Safe site by password/hhanging the default text

When I set a password for safe sites, a default text appears to the visitors. Is there a possibility to change the default text?
Now it shows:
“Dieser Inhalt ist passwortgeschützt. Um ihn anzuschauen, gib bitte dein Passwort unten ein:”
Which means: “You have to fill in the pw to see this area.” I would like to change the text, for example to inform my visitors how to get the password and write more personal.

It would be fine, if someone can tell me, in which file to change the default text.
ThX
I