The Jade Emperor felt like he had an itchy scalp. He carefully gulped and took the Sky Stamp. He tried to bond with it.
As expected, he bonded with the Sky Stamp instantly. It did not feel difficult at all.
Spiritual Treasures were hard to train if their level was high. Especially for Heavenly Spiritual Treasure. They basically belonged to the realm. More importantly, they contained the Power of Law. So, even the most basic Heavenly Spiritual Treasure was hard to train. A Daluo Golden Immortal needed millions of years to fully train a Heavenly Spiritual Treasure.
The Eastern Bell contained a Heavenly Seal that even Saints could not remove and train it!
Saints would not be willing to give away an ultimate treasure like that.