Verse 3

तत्रासौ व्योमलग्नायाः शाखायाः प्रान्तपल्लवे ।विवेश विगताशङ्कमेकाग्रं तप आस्थितः

In plain words

There, at the outer shoot of a branch that touched the sky, he entered without hesitation, and gave himself, one-pointed, to tapas.