1x01 Something Wicca This Way Comes

There's a message on the back of the spirit board that the sisters' mother Patty gave them. It says: "To my three beautiful girls. May this give you the light to find the Shadows. The power of three will set you free. Love, Mom."

1x13 From Fear To Eternity

At the end of the episode, Patty magically leaves a new message to Prue in the Book Of Shadows, saying:
"Thanks for letting them into your heart."

1x20 The Power Of Two

Phoebe and Prue leave a note to the ghost Jackson Ward so that he would come to them. Under a picture she wrote:
"Hey Jackson, let's party!"

2x01 Witch Trial

At the time of this episode, the Halliwell sisters have been witches for exactly one year. At the end of the episode, Grams magically leaves a message on a blank page of The Book of Shadows. It says: "Happy aniversary my darlings".

2x08 P3 H20

In this episode, Piper and Leo discover several love letters that Patty wrote to her whitelighter Sam. One of them says:
"Dear Sam - Where are you? It's been two weeks since you were last here. And I wonder... Are you alright? Do 'they' have you off guiding someone? And I wonder when 'they' will send you back to San Fransisco. To me. Love, Patty."

2x13 Animal Pragmatism

The Valentine's card Leo gave Piper says: "Piper, when we first met you thought I was just a handyman. Well, I'm just a handyman again. The same guy you fell in love with. The same guy who fell in love with you. For who you are, not who I think you are. Remember that and know that I'm not giving up."

3x02 Magic Hour

Piper leaves a note on the fridge saying: "I won't be home for dinner tonight, Piper."
We see it in the background but it doesn't really have any importance to the story of the episode...

3x02 Magic Hour

If the Elders find out that the sisters are planning a wedding, they will punish Piper and Leo for it. To avoid any trouble they decide not to talk about it out loud, so Phoebe holds out a board to Piper and Leo which says: "You have my blessing."

4x14 The Three Faces of Phoebe

When Cole starts acting weird, Phoebe gets unsure about marrying him. She's confused and doesn't know what to do. Piper suggests that she uses magic to get an answer, so Phoebe writes down the question: "Should I marry Cole?" to do a spell.

4x21 Womb Raider

Cole's parting letter to Phoebe: "If I'm dead right now, I know it was at your hand. No one else in heaven or hell had power over me. Please don't cry, I was dead before I met you, I was born the day you loved me, and my love for you will keep me alive, forever."

5x16 Baby's first demon

When they get to the attic, Piper finds a note that Paige left, she reads out loud: "Gone to market. Back soon." Phoebe thinks it's nothing to worry about, unfortunately Paige meant the demonic market...

5x20 Sense and Sense Ability

In this episode the sisters lose their basic senses. Piper becomes blind, Phoebe becomes deaf, and Paige loses her voice. There's a demon on the loose so the sisters have to find a way to communicate. Paige writes down everything she wants to say.

8x17 Generation Hex

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8x22 Forever Charmed

In the last episode, Piper thinks that it's a good idea to write down everything that's happened in the last eight years. They write their story in the Book Of Shadows that they pass on to their children, and later to their grandchildren.