There are two causes at work when the Stupa of Treasures appears that are stated in Many Treasures original vow. In other words there are two things that make the appearance of Many Treasures and his stupa possible. The first cause, or the first requirement was the original vow of Many Treasures. By making his vow originally he set into motion the actualization of it happening. In our own lives it would be comparable to making a determination to do something. Because of our promise or determination we put into motion the actualization of that thing we determined. This is one reason why I feel that when we take vows to practice Buddhism it is so important to really understand the significance of making that promise. We should become people of our word, doing what we promise to do, in all situations.
The second cause, which enabled Many Treasures Buddha to appear, was the supernatural powers he obtained as the result of his own practice of the Lotus Sutra. In other words Many Treasures Buddha made a vow, which he could carry out because of his accumulated benefit of practicing the Lotus Sutra. Many Treasures Buddha, wishing to repay his gratitude for the many benefits he had obtained, promised to appear whenever the Lotus Sutra was taught, and he was able to do this because he received the merit and made the promise.
In our own lives, we have the hidden treasure, the gem of Buddhahood, which we can ignore and let lay dormant. On the other hand we can choose to make a vow, or a determination, to manifest and then carry out the necessary activities to actualize the vow to manifest our Buddhahood. All this we can do through our faith in the Lotus Sutra.
Lecture on the Lotus Sutra