पूर्वाभ्यासेन तेनैव ह्रियते ह्यवशोऽपि सः। जिज्ञासुरपि योगस्य शब्दब्रह्मातिवर्तते ॥

pūrvābhyāsena tenaiva hriyate hyavaśho ’pi saḥ jijñāsur api yogasya śhabda-brahmātivartate

By that former practice he is irresistibly swept away. Only wishing to know yoga, even the seeker after yoga goeth beyond the Brâhmic world;

In plain words: Krishna says the habits from that earlier practice pull the person strongly back to the spiritual path. Even someone who only wants to learn about yoga goes beyond simply following religious rituals.