The search for "slipped" delivered 2 verses in 2 songs on 2 records.
The dragon searched for the following: "slipped" as keywords
Here are the matching verses:
Dio: Master Of The Moon
5. The Man Who Would Be King
We never got an answer, the question slipped my mind
I've been so busy killing, I haven't found the time
Dio: The Last In Line
5. One Night In The City
The someone opened doorways
And Johnny slipped away
Running for the bright, where dark is always light
But there's no day