Shloka 18
Keśava-tattva-kathana
On the Principle of Keśava: Cosmogony and Divine Epithets
उपस्थितकृतौ तौ च नासिकाग्रमधो भ्रुवो: । भ्रुकुट्या चैव मनसा शनैर्धारयतस्तदा
upasthitakṛtau tau ca nāsikāgram adho bhruvoḥ | bhrukuṭyā caiva manasā śanair dhārayatas tadā ||
毗湿摩说道：“其后二人摄身端坐，微蹙双眉以凝神，目注眉下鼻端。继而又将五种气流——普拉那、阿帕那、乌达那、萨玛那、维亚那——安置于心中；如是安住，便令心与普拉那、阿帕那相合，并使那由心所持之息，稳住于两眉之间。”
भीष्य उवाच
Educational Q&A
The verse teaches disciplined inward concentration: steadying the mind, regulating the vital currents (the five prāṇas), and fixing awareness through a focused gaze and breath-control so that the mind becomes stable and fit for higher realization.
Bhīṣma describes two practitioners entering a yogic state: they fix their gaze at the nose-tip beneath the brows, gather and place the five life-winds in the heart, unite mind with prāṇa and apāna, and then stabilize that combined focus at the space between the eyebrows.