The three dhāraṇīs primarily featured on this website are the Dhāraṇī of Amitāyus Tathāgata, the Dhāraṇī of Maitreya Bodhisattva, and the Dhāraṇī of Humane Kings. I have identified this three to be the most suitable for the propagation of the Buddhadharma as they tackle the various concerns, needs, and aspirations of a typical householder. While supreme enlightenment is the ultimate goal, our material conditions and our merit are also incredibly important because they make practicing easier and enable us to create environments conducive to the propagation of the Buddhadharma.
Dhāraṇī of Amitāyus Tathāgata
The first of the three dhāraṇīs is that of Amitāyus Tathāgata. Studying scriptures and engaging Buddhist concepts aside, this alone suffices in bringing us to the fullness and completion of the path to liberation. Why? This dhāraṇī provides protection, secures our needs, and clears away obstacles to the path. Failing at attaining liberation in this lifetime, we are reborn in Sukhāvatī, where we will practice the path without the troubles characteristic of saṃsāra. Thus, the dhāraṇī is the perfect companion on the path to liberation. It has a failsafe for if, for whatever reason, we do not become enlightened in this life.
Additionally, this dhāraṇī is concerned with the individual. In the schema of our propagation of Buddhadharma, there is the practice for the self, the practice for those who are close to us, and the practice for others generally. This dhāraṇī is the practice for the self and benefits oneself primarily. While this is not its only function, it is the focus of the benefits and promises attached to the upholding of this dhāraṇī. This is why if there's one mantra that we should be reciting everyday, especially if we have no guidance or support from a qualified master, this is the one that should be one.
Dhāraṇī of Maitreya Bodhisattva
The second of the three dhāraṇīs is that of Maitreya Bodhisattva. This is the mantra for those who are near us, whether by bond or by physical proximity. While it has benefits for those who recite and uphold it, it is especially potent for those who are helpless and unable to practice the Buddhadharma themselves, such as non-Buddhists, animals, and the various unseen beings that we may inevitably encounter throughout our lives.
This mantra guarantees safety from the lower realms, namely animals, hungry ghosts, and hell beings. By reciting and hearing this dhāraṇī, the doors and potentialities to be reborn in any of these realms are shut close. However, while it primarily benefits us in that way, it also has the ancillary function of providing us our needs and wants through reciting and upholding it. Thus, it has two purposes, but it is an excellent practice for benefitting those who are near us.
Dhāraṇī of Humane Kings
The third dhāraṇī is that of Humane Kings or, more specifically, the dhāraṇī from the "Prajñāpāramitā Scripture for Humane Kings Who Wish to Protect Their States." It is found in the seventh chapter of the aforementioned sūtra, which is titled "Receiving and Keeping This Scripture." From this, it can inferred that upholding this dhāraṇī is similar to upholding the entire sūtra. It should be noted that this sūtra was expounded specifically to benefit countries so that the Buddhadharma can be established and prosper, though it contains important teachings on prajñāpāramitā.
You might be wondering, "I'm not a king, so why should this dhāraṇī concern me?" A king, in reality, is any person who has the power and capacity to establish the Buddhadharma. By upholding this dhāraṇī, you are essentially being consecrated by the buddhas themselves as a king. One of the promises for this dhāraṇī is that all the buddhas of the ten directions will always be "supportive and protective" of the person reciting and upholding the dhāraṇī, which allows us to propagate the teachings further as we are under the protection of the buddhas themselves.
This dhāraṇī is our practice for others. It is the ultimate expression of bodhicitta, of mahākaruṇā, and of prajñāpāramitā itself. We recite this mantra with the intention of benefitting more than just ourselves, our loved ones, or those around us, but our communities and societies as a whole. Whenever we recite this mantra, we are shouting to the entirety of saṃsāra that suffering will end, that we are on the path to ending the suffering of all beings, not just ourselves. A bodhisattva, pure in conduct and true to their vows, recites and upholds this dhāraṇī while they go on with their other activities, such as studying, helping others, and so on.
Conclusion
In summary, these three dhāraṇīs were chosen for their scope and application. The intention is that we have three separate but still interconnected practices. By reciting and upholding these three dhāraṇīs closely every single day, the practitioner gets to benefit oneself, those who are nearby, and everyone else simultaneously. At the end of the day, we are bodhisattvas on the path to buddhahood. Thus, we need to be capable of easing the suffering of other beings. Fortunately, we have methods at our disposal that can aid us in doing so. We only need to apply them diligently as we practice in this lifetime with the confidence that it is our last [as non-enlightened beings].