Even when feeling intense pleasure, do not give away the core of your heart.

Those who equally accept pleasure and pain, and are not disturbed by them, are said to be worthy of immortality. This does not mean eliminating sensations or becoming numb to everything. It means experiencing pleasure and pain without allowing them to dominate one's heart.

Krishna calls Arjuna "the bull among men" and the best of heroes. He is not only addressing his current state of sorrow, but also calling forth the inherent strength that allows him to transcend dualistic experiences. An equal-mindedness that is not swayed by either pleasure or pain leads to immortality, which is the realization of the true nature of the soul.

Japanese Translation from the Geeta Press Edition - Chapter 2, Section 15: "One who is equal in joy and sorrow is worthy of immortality."

If one ignores and transcends the contact between sensation and its object, what results will occur?

In anticipation of this question, the master would say:

Sanskrit original text

यं हि न व्यथयन्त्येते पुरुषं पुरुषर्षभ ।
समदुःखसुखं धीरं सोऽमृतत्वाय कल्पते ॥ १५ ॥

Romanization

yaṃ hi na vyathayanty ete puruṣaṃ puruṣarṣabha |
samaduḥkhasukhaṃ dhīraṃ so 'mṛtatvāya kalpate || 15 ||

Arjuna, one who sees pain and pleasure as equal, and is not troubled by these contacts, is worthy of immortality. (15)

In this section, the invariable word "Hi" is used to indicate a reason. Its purpose is to explain why one should avoid sensory perception and contact with its object.

Ṛṣabha means "the best" or "the most excellent." Therefore, the compound word Puruṣarṣabha here signifies the most heroic and strongest person. By calling Arjuna Puruṣarṣabha in this verse, the speaker is saying that for Arjuna, who is the foremost among heroes and the strongest among people, indifference to pleasure and pain should be an inherent quality. Therefore, transcending all these dualistic experiences should have been quite easy for him.

The word "Dhīram" is generally used to refer to a soul that has realized God. However, it can also mean a soul that possesses sufficient qualifications to realize God. Here, it refers to a practitioner who has reached a mature state in the practice of Samkhya Yoga, which is yoga through knowledge.

The term Samaduḥkhasukham, which means "one who is equal to both pain and pleasure," is used to indicate the essential qualification of a Dhīra.

A person who views both pleasure and pain with equanimity, that is, someone who considers both experiences as transient and does not make distinctions between them, is a Dhīra. Only such a person can overcome them without being affected by them.

In the previous section, the sensations and their contact with objects of sense, which were represented by the word "Mātrāsparśāḥ," are again referred to in this section using the word "Ete," meaning "these."

Furthermore, by saying "one who is not troubled by these contacts," it indicates that: A practitioner reaches a certain state through repeated and continuous practice of overcoming attraction and repulsion, joy and sorrow, which arise from contact with and separation from objects of sense. In that state, no matter which sensation comes into contact with any object of pleasure, no reaction arises.

If a person does not experience emotional turmoil or pathological feelings, they are considered to be a Dhīra, that is, a wise person who has achieved equanimity in the face of suffering and pleasure.

"To become one worthy of immortality," the Lord says, "is to possess a mind like that described above, a wise person who remains undisturbed and unaffected by any contact, thereby becoming eligible for Moksha, or union with God, and soon succeeding in directly realizing God."