Piper deduces that Abraxas must be reading the Book of Shadows backwards, because the spell used to vanquish Jeremy was at the back of the book; originally, the spell was on the back of their spirit board, not in the book. She also says the "Woogyman" Spell was just before that, but Phoebe added the spell somewhere in the center of the book.
When Phoebe walks in on Piper making out with the guy from the bank, Piper freezes him with his mouth open but in the next shot his mouth is closed, and then open again.
Within the first minute, Phoebe walks in on Piper in a compromising position with someone from the bank and Piper freezes him, except the gesture and sound takes place almost a full second before he stops moving.
When the show starts and they are in the attic, you can see someone crawl behind the boxes.