In plain words
equal in honour and dishonour, equal toward friend and enemy, and who has abandoned all undertakings—is called one who has gone beyond the guṇas.
Word for word
Equal in honour and dishonour, equal toward the sides of friend and foe, one who has given up all undertakings: he is called one who has gone beyond the guṇas.
मानापमानयोस्तुल्यस्तुल्यो मित्रारिपक्षयोःसर्वारम्भपरित्यागी गुणातीतः स उच्यते
Other commentaries
The commentators
▸Bhagavadgītābhāṣyam
किञ्च —
मानापमानयोः तुल्यः समः निर्विकारः ; तुल्यः मित्रारिपक्षयोः, यद्यपि उदासीना भवन्ति केचित् स्वाभिप्रायेण, तथापि पराभिप्रायेण मित्रारिपक्षयोरिव भवन्ति इति तुल्यो मित्रारिपक्षयोः इत्याह । सर्वारम्भपरित्यागी, दृष्टादृष्टार्थानि कर्माणि आरभ्यन्ते इति आरम्भाः, सर्वान् आरम्भान् परित्यक्तुं शीलम् अस्य इति सर्वारम्भपरित्यागी, देहधारणमात्रनिमित्तव्यतिरेकेण सर्वकर्मपरित्यागी इत्यर्थः । गुणातीतः सः उच्यते ‘उदासीनवत्’(भ. गी. १४ । २३) इत्यादि ‘गुणातीतः स उच्यते’(भ. गी. १४ । २५) इत्येतदन्तम् उक्तं यावत् यत्नसाध्यं तावत् संन्यासिनः अनुष्ठेयं गुणातीतत्वसाधनं मुमुक्षोः ; स्थिरीभूतं तु स्वसंवेद्यं सत् गुणातीतस्य यतेः लक्षणं भवति इति । ॥ २५ ॥
In plain words
And there's still more —
'Equal in honor and dishonor' simply means unmoved, unchanged either way. 'Equal toward friend and foe': some people only look neutral because that happens to be their own private stance, but this is different — even from someone else's point of view, this person genuinely treats both sides the same, and that is what 'equal toward friend and foe' really means. 'One who has given up every undertaking': any action aimed at some seen or unseen result counts as an 'undertaking', and this is someone whose very nature is to let go of every one of those undertakings — someone who has set aside all action except whatever is simply needed to keep the body alive. And wherever the text calls someone 'one who has transcended the guṇas', from 'like one who stays neutral' (Bhagavad Gītā 14.23) all the way through 'he is called one who has transcended the guṇas' (Bhagavad Gītā 14.25), everything said there — whatever part of it can actually be practiced through effort — that much is the discipline a liberation-seeking renunciate must genuinely take up. But once it has become second nature, something you simply know within yourself without effort, that is no longer a practice at all — it is simply what defines the ascetic who has truly gone beyond the guṇas.
Close to the Sanskrit
Moreover —
'Equal in honor and dishonor' [means]: the same, unchanged. 'Equal toward the sides of friend and foe': although some who are indifferent act so from their own inclination, nevertheless, from another's viewpoint, they appear as if [equal] toward the sides of friend and foe — thus [the verse] says 'equal toward the sides of friend and foe'. 'One who has abandoned all undertakings': actions aimed at seen and unseen ends are undertaken — thus [they are] undertakings; whose nature is to abandon all undertakings — thus 'one who has abandoned all undertakings', [meaning] one who has abandoned all action except what is merely the cause of sustaining the body: this is the meaning. 'He is called one who has transcended the guṇas' — from 'like one who is indifferent' (Bhagavad Gītā 14.23) and so on, up to and including 'he is called one who has transcended the guṇas' (Bhagavad Gītā 14.25) — whatever has been said, to the extent it is achievable by effort, that much is to be practiced as the means to transcending the guṇas by the renunciate who seeks liberation; but once it has become firm, self-evident to oneself, that becomes the defining mark of the ascetic who has transcended the guṇas — so it is.