[adwade]

This is how it's done for vB 3.8, so I suspect v4 is very similar...

go to AdminCP -> Languages & Phrases -> Search in Phrases. Once there, enter the word notify into the Search For Text field and choose the Phrase Variable Name Only radio button. The results should show the notify phrase, which contains the body of the subscribed thread e-mails. Click the Edit button on the right, then click the Copy Default Text button near the bottom. This will copy the default contents of the phrase to the textarea at the bottom, and allow you to customize it.

Remove the following text from the textarea, and click Save:

Here is the message that has just been posted: *************** $pagetext ***************