tatra tam buddhi-samyogam
yatate ca tato bhuyah
"On taking such a birth, he revives the divine consciousness of his previous life, and he again tries to make further progress in order to achieve complete success, O son of Kuru."
Kuru nandana = son of Kuru dynasty [Arjuna], paurva dehikam = in the past body's [ previous birth], buddhi samyogam = attachment of knowledge, labhate = gets back. In the last birth, this person performed yoga; but discontinued, as he was distracted by some inferior desires. That yoga, however short he had performed, had power, because he practiced it as it was the advice of the Lord. This power got him the inferior desires he wanted and after fulfilling that desire, got him a birth in a family, where the atmosphere was conducive to restart the yoga, he had discontinued in the earlier birth. This is like we remember all those which happened before we went to bed. Tatra tam = =[in this birth where he is born after enjoying all desires he wanted while doing yoga in the last birth, he gets the same ] that knowledge in this body. Bhuya = again, yataeta ca = he restarts. The imprints of the last birth are all available now in the present birth, and he is able to start yoga again. To get back those imprints, what is needed is something to trigger in the mind. This triggering happens by his birth in a noble family where there are yogis and so a conducive atmosphere is created. Samsiddhau = in order to practice yoga. In the family where he is reborn, people are available to advice him properly to restart yoga. It is like a person who knew bicycling, and had discontinued for, say, 15 years. When he wants to ride bicycle after that gap, all he needs is a word of encouragement only and he need not go through the entire process of learning to drive. This is because that learning is already imprinted in him and the encouragement only triggered. Contrarily, if there is discouragement, then this person might not attempt to drive the bicycle. Similarly, this person gets encouragement from a family where he is reborn, to practice yoga. Being born in such families he is able to observe their practices and so is able to grasp and restart. As a continuation of this sloka is the first half of sloka 44 and so we will see that also:
hriyate hy avaso ’pi sah
"By virtue of the divine consciousness of his previous life, he automatically becomes attracted to the yogic principles"
Sa = that yogi, who had discontinued the yoga in his last birth and is reborn in the family where yoga practicing is encouraged, tenaiva = that, purvabhyasena = practice followed in previous birth, avesa'pi= [even if he does not show inclination] spontaneously, hriyate = is dragged into [yoga]. Purvabhyasena can mean by the same interest or by the same vairagya or by the same knowledge of atman or by the same karma yoga or by the same interest with which the yoga was practiced, in the previous birth. We also observe this, when we are dragged into certain activities almost involuntarily. It is like a darshan of the Lord in Thirumala. Our effort is only to go to the queue complex, and afterwards automatically we are pushed and pulled and made to have a darshan of the Lord and we come out with prasadam in our hands! The earlier birth vasanai would drag him into yoga in this birth and he would complete yoga and have atman sakshatkaram. This can be seen in the legend of Jatabharatha. He was practicing yoga, but suddenly developed attachment to a young deer and while dying, his mind was full of deer only. He was born as a deer. But after this deer died, he was born as a yogi and continued his yoga. He did not have any more births after he was born as a deer, and immediately in the next birth he was able to start yoga. All these imprints are activated because of the blessings of the Lord.