गमयित्वान्यमाक्रममाक्रम्यात्मानमुपसं-हरति ॥ ३ ॥
In plain words
...lets that go, takes hold of the next foothold, and draws itself fully in. That is the third verse.
Close to the Sanskrit
...having dispatched [the darkness], having stepped upon another foothold, it draws itself in. || 3 ||