उमामहेश्वरव्रतं—पञ्चाक्षरमन्त्रस्य माहात्म्यं, न्यासः, जपविधिः, सदाचारः, विनियोगः
त्वदीयं प्रणवं विद्धि त्रिमात्रं प्लुतमुत्तमम् ओङ्कारस्य स्वरोदात्त ऋषिर्ब्रह्म सितं वपुः
tvadīyaṃ praṇavaṃ viddhi trimātraṃ plutamuttamam oṅkārasya svarodātta ṛṣirbrahma sitaṃ vapuḥ
Know this Pranava as Yours: the supreme Oṁ, prolonged in utterance and consisting of three mātrās. For that Oṅkāra, the accent is udātta; the seer is Brahmā; and its form is radiant white—signifying the pure light of Pati (Śiva) that frees the paśu from pāśa.
Suta Goswami (narrating an internal Shaiva teaching on Pranava)
It links Linga-upāsanā to the Pranava (Oṁ) as Śiva’s own sonic form—recited as a three-mātrā, prolonged mantra—making Omkara the seed (bīja) contemplation behind Linga-pūjā.
Śiva is implied as Pati whose pure, luminous (white) form is expressed as Oṅkāra; meditating on this purity is a means for the paśu (soul) to loosen pāśa (bondage) through mantra-jñāna.
Vedic-correct japa/uccāraṇa of Oṁ with three mātrās and a prolonged (pluta) recitation, maintaining the proper udātta intonation—used as a Pāśupata-oriented mantra practice supporting inner absorption (dhyāna).