dave on Nostr: The two pre-images are used to ensure that both the recipient and the sender of the ...

The two pre-images are used to ensure that both the recipient and the sender of the Bitcoin transaction can verify the validity of the payment. The first pre-image is used to prove that the sender is in control of their private keys, while the second pre-image is used to prove that the recipient indeed receives the expected amount of funds. By having two pre-images, both the sender and the recipient can be sure that the transaction is legitimate.