Thanks for pointing that out to me.
Actually, the Four Powers come from a sutra. They are not, strictly speaking, Vajrayana in essence. However, in this sutra, they are known as the Four Dharmas.
The Sutra of the Exalted Teaching on the Four Dharmas
Gya-gar ked-du: Arya Chatur Dharma Nirdhesha Nama Mahayana Sutra
Bod ked-du: Phak-pa Cho-zhi Ten-pa Zhe-ja-wa Theg-pa Chen-poi Do
I prostrate to all the Buddhas and Bodhisatvas.
Thus once have I heard:
The Bhagawan was residing in the assembly place of the Gods known as Excellent Dharma within the Heaven of the 33 along with a great assembly of 500 monks and an immensely great many Bodhisatvas [and] Mahasatvas, including Maitreya and Manjushri. Thereupon, the Bhagawan granted teaching to the Bodhisatva, Mahasatva Maitreya [saying]:
“Maitreya, if a Bodhisatva [or] Mahasatva has four Dharmas, He [or She] will vanquish non-virtuous actions that have been performed and accumulated. What are these four? They are as follows: the power of full application of strong remorse, the power of full application of the antidote, the power of restoration, [and] the power of the support.
“In terms of this, full application of strong remorse [means having] much regret for having engaged in [whatever] non-virtuous action [has been done]. In terms of this, the full application of the antidote [means having] strong, vigorous diligence in [performing] virtuous actions immediately after having engaged in non-virtuous actions. In terms of this, the power of restoration [means developing] unbreakable restraint by means of sincerely making a vow [not to perform that non-virtuous action ever again]. In terms of this, the power of the support [means] going for refuge in the Buddha, Dharma, and Sangha and not giving up Bodhicitta. If one has these [four] powers, the destructive power [of non-virtuous deeds] cannot prevail. Maitreya, if a Bodhisatva [or] Mahasatva has these four Dharmas, he [or she] will vanquish whatever non-virtuous actions have been performed and accumulated. Bodhisatvas [and] Mahasatvas should continuously [and] copiously read, recite, think about, meditate on, and practice this sutra. In this way, the fruit of non-virtuous actions will not be able to appear.”
When the Bhagawan had said this, the Bodhisatva, Mahasatva Maitreya, those monks, those Bodhisatvas, those children of the Gods, such as Indra, and the entire assembly rejoiced and praised the words spoken by the Bhagawan.
[Thus] the Mahayana Sutra known as the Exalted
Pema Chophel པདྨ་ཆོས་འཕེལ