Bhagavad Gita Chapter 5, Verse 27

स्पर्शान्कृत्वा बहिर्बाह्यांश्चक्षुश्चैवान्तरे भ्रुवोः | प्राणापानौ समौ कृत्वा नासाभ्यन्तरचारिणौ ||

sparśān kṛtvā bahir bāhyāṁś cakṣuś caivāntare bhruvoḥ prāṇāpānau samau kṛtvā nāsābhyantaracāriṇau

Shutting out external contacts and fixing the gaze between the eyebrows, making the incoming and outgoing breath equal, moving within the nostrils.

Krishna describes a practical meditation technique: shutting out external contacts (sparśān kṛtvā bahir bāhyān), fixing the gaze between the eyebrows (cakṣuś caiva antare bhruvoḥ), and making the incoming and outgoing breath equal (prāṇāpānau samau kṛtvā), moving within the nostrils (nāsābhyantaracāriṇau). This is a practical technique for controlling the senses and mind. By withdrawing from external contacts, focusing the gaze, and balancing the breath, the yogi gains control over the senses and mind. This technique supports the practice of karma yoga by helping develop the inner discipline needed to remain detached while acting.