Mahāhradānusandhānānmantravīryānubhavaḥ महाह्रदानुसन्धानान्मन्त्रवीर्यानुभवः (sūtra 22)
Mahā – great; hrada – lake (could also mean river Ganges); anusandhānāt – union through mind;mantra – mantra; vīrya – efficacy or potency; anubhavaḥ - experience.
Great lake means the reservoir of divinity, the Supreme consciousness. A yogi, by establishing a link though his mind with Supreme Consciousness, which is also known as the embodiment of entire divinity experiences the efficacy of mantra-s, the creative source of sound. Sound has the capacity to create. The divine sound of ॐ is internally experienced in anāhat cakra. Sound originates from Śaktī; hence She is called Śabda Brahman. Only due to acts of Śaktī, subtle becomes gross. For example, combination of letters gives rise to words that become the vehicle of understanding and knowledge.
The ocean of divinity is localized within. This is called I consciousness. This I does not mean ego. Ego is the cause for identifying oneself as a different entity from Śiva. In this context, I refer to Śivaconsciousness. The subtle form of Śiva consciousness is manifested in the form of different shapes and forms due to the creative power of Śaktī, who always stands united with Śiva. The one without the other becomes inert. She knows and understands the will of Śiva to create. She causes the creation through different energy levels, one of them being the sound. The collective sound of all the fifty one letters leads to ahaṁ (अहं), the foundational principle of I consciousness. This is different from ego, the cause for creation of individual identity. I consciousness is Śiva consciousness.
Union through mind is the union of individual consciousness with Universal consciousness by focusing within. Introverted focus leads to this conjugation, resulting in the experience of the Supreme power of autonomy of Śiva, in the form of highly potent Śaktī, from where manifestation unfolds extroversively. Spanda Kārikā (II.1) says, “Pure aspect of the universe consisting of mantra and others arises from that principle only is manifested by force and is merged in that only”. This means both creation and dissolution happens through Supreme I consciousness. In the process, there are two unions. The first one is the mental union with Śaktī, where the power of yogi’s consciousness gets energized to become eligible for union the highest level of pure consciousness, the Śiva consciousness. Without experiencing the first union, the final union is not possible.
With this 22nd sūtra, the first chapter of Śiva Sūtra-s is completed. In trika philosophy there are three principal paths called upāya-s. They are śāmbhavopāya, śāktopāya and āṇavopāya. Out of the threeśāmbhavopāya is considered as the highest where a yogi enters Supreme Divine Consciousness with divine intervention. Here, a yogi need not do much on his own. In śāktopāya mental contemplation becomes important. The yogi’s practice and perseverance are significant here. Ināṇavopāya, a beginning is made through the means of breath control, mantra-s, etc. The fist twenty two aphorisms deal with the highest of upāya-s, the śāmbhavopāya. The next section consisting of ten sūtra-s deals with śāktopāya.