We are in the midst of Ganesh Chaturthi, so it is good to focus on some Ganapati sadhana during this time. In all our sadhana, we give importance to Ganapati and he is the first Devata invoked, as all obstacles for the sadhana are removed. However, Ganapati should not just be seen as an "intro" work to our other sadhana, as there are whole practices dedicated to him. In fact, when understanding the nature of Reality to be complete (as it is), spiritual practice can be seen as nothing other or more than removing obstacles. Ganapati's sadhana contains many different rupas which accord to different intents and resonances. Ganesh is also known as the lord of new beginnings, which in common terms people usually relate to starting various endeavors. However, for the sadhak who lays bare every session, surrenders to the marrow and is willing to meet death, then new beginnings are every day...every moment. Wishing all the best for this auspicious period.
During eclipse, the effects of all actions are multiplied, so it is important to be mindful during these periods. For sadhaks, an eclipse is a very good time to focus on sadhana. Both because of the multiplying factors during eclipse and the nature of mantra siddhi (which generally takes accumulation), mantra sadhana can be very potent and productive during these times. Sadhana is multiplied by 10,000 during eclipse (and could even be more with certain other factors), so to recite a stotra once is like doing it 10,000 times. In tantric sadhana, a vidya mantra usually has certain requirements to both make the mantra "active" and also to perfect it. Therefore, during an eclipse, one may accomplish in hours what would have taken months or even years. A mark of wisdom is being both efficient and skillful, so taking advantage of an opportunity (like an eclipse) should be seen in such a light. Howerver, one shouldn't approach such endeavors with a greedy mind, as doing so would only multiply the effects of one's greed. Rather, one should understand efficiency of action while also having pure motive and nobel intent. To do such multiplying sadhana with the mindset that it is being done for the liberation of all has an incalculable beneficial effect. There are several ways that one may structure a sadhana during eclipse. One may sit through the entire eclipse period (starting when partial begins till complete finish), but it is often better to break into several sessions so one can stay sharp and more focused. Three sessions work well, with one in the beginning of the eclipse period, a longer one running during greatest eclipse, and then a final one before the eclipse finishes. A sadhak generally has different elements of their sadhana and Vidyas that they normally work with, so the structure of the eclipse sadhana needs to be clear beforehand. Some decide to just work on one element during an eclipse, while others incorporate their entire sadhana mandala. It is usually best to decide on a focus for the eclipse sadhana, which will be one or two elements that will get special attention. However, one can still do their entire sadhana so that all elements are empowered, while going deeper with those aspects of special attention. One is just doing a minimum of certain elements, while doing much more of those selected. Sadhana during eclipse can push one to a new level in a Vidya, so it is good if one can intuit the timing of what it is best to focus upon.
Most real growth on the spiritual path comes when we allow ourselves to go beyond our comfort zones. This is because a comfort zone is mainly a "ground" that the I sense clings to and feels secure in, and by removing those "grounds", one is left with the requisite openness for wisdom and growth. A comfort zone can range from subtle and psychological to more substantive and material forms, but most real demonstrations of stepping outside of a comfort zone should include a material actualized form. The reason for this, is that for most people, a lingering comfort zone is self-deception which attributes qualities that haven't been demonstrated. Moreover, one whose inner actions also contain a practical application have a quality of confidence (and something unstatable), which strictly "mental warriors" ("i could do that") can never achieve. Many ancient and indigenous cultures understood this wisdom and had/have various rites of passage. (To the extent that modern culture has rites of passage, they are mostly vapid and serve a business and consumer model.) Nowadays, a lot of what passes as spirituality is more wellness and self improvement, whereby one is made to feel more comfortable and have a "better" attachment to the various grounds of self. Often, people with no real life stresses (in a gather food and a lion might kill me way), turn their unspent/frustrated energies into neurotic anxieties and believe what they need is comfort (via "spa" spirituality). However, what they really need is to be challenged and pushed beyond their comfort zone patterns (which are the very patterns of their neurosis). Even those who have been on a path for sometime should be vigilant to see where/when the i sense settles into patterns/grounds. It is not unusual for lofty concepts to turn into comfort grounds, nor for Tantrics to use Deities to hide behind. Even openness can become strategic. Of course, a true and balanced path should include both periods of pushing and settling (expanding and assimilating), and as one progresses, one gets a better understanding of timing. A Guru or guide are also important in helping a sadhak understand what actions are required at a given juncture. However, one can hardly go wrong by continually stepping into the depths and challenging themselves which gives rise to true humility.
Ucchistha Chandalini is the "outcaste" Devi who governs the remainders or left overs in a puja or sadhana. As Matangi, the energy is also associated with magnetizing principles and non-divisive wisdom. Mantangi as a particular all red form is also known as Sumukhi Devi, and is described as being seated on a corpse holding a kapal and sword. It is said that sadhaks who perfect the Vidya of Ucchitha Chandalini need not worry over errors of commission or omission in their sadhanas, as even "errors" would be seen as remainders and thus offerings. Indeed, while it is easy to conceive of remainders/left overs in terms of an external puja (via the various articles of worship), the Vidya is most profound in its interactions with the inner qualities of a sadhak. In our sadhana, we are likely to have left over aspirations that we've been unable to properly channel, energies that we've not be able to assimilate properly, or lingering elements of all sort, and including a practice of Ucchishta Chandalini brings everything into balance and perfection (imperfection as perfection). Also in our sadhana, we are likely to make some errors, maybe some of our mantras are not correct (or we missed the proper amount), or our concentration isn't sharp, or our compassionate intent isn't as expansive as it should be, but in these cases (and others) Sumukhi Devi excepts these "mistakes" as offerings. Inherent in this Devi is a deep understanding of unitive wisdom (one taste), which is the true siddhi that the sadhak needs to abide as. So one shouldn't just understand this Vidya as "offering the remainder to the Divine to make it Divine", but should come to the unitive understanding of everything as Divine expression. In this way, like in other areas of Tantra, we unite in/as the Deity and operate from their/that perspective. Ucchista Chandalini functions in the subtle centers and the various yogic processes which accompany sadhana, so "remainders" or "left overs" also refers to energies in our subtle channels. Therefore, the wisdom of the Devi is also functional in our subtle experience. Uccishtha Devatas of all sort are said to be quick to respond, and many of their sadhana requirements are more easy to accomplish than other deities. As one gains experience in the Vidya, then it begins to permeate one's day to day life. For those interested in benefiting others, it can be an important Vidya both in terms of how one's own expression is "received" and also in clearing obstructions in others. If in a moment we are conventionally unskillful in a daily interaction, the knowledge of the Vidya can make it skillful none the less (it will somehow take the edge/remainder off and communicate something positive.) One may think that as one gains wisdom, that one will work with Ucchishta Devatas less (as presumably there are less energetic remainders), but at a certain levels of understanding, one views all manifest existence as a remainder of sort, and certainly one's own life (via interaction with the world) can be seen as such.