Getting into the verses one by one. We have already got an idea of verse 1 from the introduction to the chapter. It is Arjuna’s query to Shri Krishna about which Path is best. Posting below FB post of Shri Sugavanam Krishnan ji and his comments from his blog https://advaitavedaanta.wordpress.com/. Will also try and add what Sri Alladi Mahaeva Sastri explains from Sankara Bhashya.
Bhagavad-gītā kiñcitadhītā – One śloka a day – chapter 12.01
अर्जुन उवाच |
एवं सततयुक्ता ये भक्तास्त्वां पर्युपासते |
ये चाप्यक्षरमव्यक्तं तेषां के योगवित्तमाः || १ ||
arjuna uvāca |
evaṁ satatayuktā ye bhaktāstvāṁ paryupāsate |
ye cāpyakṣaramavyaktaṁ yeṣāṁ ke yogavittamāḥ || 1 ||
In this manner, (there are) those devotees who, abidingly committed, meditate upon you and also (there are) those who seek you as one who is not subject to decline and not available for objectification. Who among them are the greatest knowers of yoga?