katham vidyam aham yogims
tvam sada paricintayan
kesu kesu ca bhavesu
cintyo ’si bhagavan maya

"O Krishna, O supreme mystic, how shall I constantly think of You, and how shall I know You? In what various forms are You to be remembered, O Supreme Personality of Godhead?"

He asks what all he should know more about the Lord? In what way he should understand Him? What are the various auspicious qualities [கல்யாண குணங்கள்] He possesses? What are His commanding Powers? Aham = I [Arjuna, the ignorant and about to start Bhakti yoga], katham vidhyam = how am to know [about the Lord]? Now Arjuna introduces himself. Yogim = person about to start Bhakti yoga. We can not take the word to mean Bhakti yogi, as that person would already know the Lord and he does not need any clarification. So Arjuna wants to know what all a person, who is going to start Bhakti yoga, should know about the Lord. Tvam = You [Sri Krishna, the Supreme Lord, meditated by yogis], sada = always, paricintayan = remembering. Arjuna wants to know how he can always remember the Lord to start the Bhakti yoga. Always remembering is a stage which the matured Bhakti Yogi would attain and it is just like sakshatkaram, when he would see the Lord whether he closed or opened his eyes. But Arjuna is not in that stage and so this meaning can not apply here. Arjuna is in the initial stage of Bhakti yoga and so he is asking the Lord how to constantly remember Him. This is the first part of the sloka. Arjuna wants to know by which auspiciuos attributes of the Lord he should start Bhakti yoga. The Lord has many, many auspicious qualities, which are all opposed to blemishes. Arjuna wants to know by which qualities he should meditate. Kesu kesu = by which and which, bhavesu = matter, bhagavan asi = Lord [Sri Krishna] is, cintya = object of thought or mind, maya = by me [Arjuna]? Arjuna wants to know in which matter the Lord dwells. What way we should meditate on the Lord as the dweller in and commander of objects? Arjuna, in brief, asks what are the Aiswarya of the Lord, over which He has absolute command. We are to know these two things - His auspicious attributes and His Aiswarya on which He has command. In the Vaidhika sampradhayam, knowing the auspicious qualities is very important. The Lord has endless auspicious qualities. If the Lord were without qualities, we would find it impossible to be in devotion or Bhakti. We go to a temple and pray. We regard Him as our Parents to show mercy; or, we seek His pardon; we seek His affection, etc. If these qualities were not in Him, we would be scared to approach Him. He has shown different qualities to various devotees like Vidura, Gopikas, Sanjaya, Hanuman, Sugreeva, Vibheeshana, etc. Arjuna wants to know what are qualities should be attributed to the Lord to worship Him. Similarly, He wants to know His Empire in which He dwells and commands. Swami Vedanta Desika in his Tatparya Chandrika says that in the earlier Two slokas the Lord had listed some Twenty items as under His control - like buddhi, gyana, asammoham, kshama, satyam, dhama, and many materials. Now if Arjuna asks in which He dwells and controls, apart from what all He listed earlier, what other matter are there at His command? Arjuna is going to further explain his request in the next sloka. 
                                                                                                          (continued)