यतेन्द्रियमनोबुद्धिर्मुनिर्मोक्षपरायणः।विगतेच्छाभयक्रोधो यः सदा मुक्त एव सः॥
yatendriya-mano-buddhir munir mokṣa-parāyaṇaḥ vigateccā-bhaya-krodho yaḥ sadā mukta eva saḥ
Word by word
The verse says
— the sage with senses, mind and understanding held steady, aiming at release, with wanting, fear and anger gone: he is free already, always.
In plain words
The sentence that began in the last verse lands here.
And the landing is in the present tense. Sadā mukta eva saḥ — he is always, already, free.
Not will be. Is.
Where you've felt this · in study
You do the same ten minutes every morning for a year and nothing dramatic happens. Then you notice you have not lost your temper in a month, and you cannot point at the day it changed.
Going deeper
The tense is the whole verse.
Everything in the chapter could have been read as a programme: do these things, and afterwards you will be free. This line refuses that reading. The person described is free already, and always was, and the practice did not manufacture it.
Mokṣa-parāyaṇaḥ — having release as the highest aim. So there is still aiming going on. The freedom is not being treated as a reason to stop.
Holding both of those at once is the difficulty, and the Gita does not smooth it. You are aiming at something you already are, and the aiming is not pointless.
The nearest ordinary parallel is a skill in the hands. Nothing was added to the body over that year of practice. Something stopped getting in the way, and now the thing that was always possible happens.