In plain words
The poet, to the Lord: Once you measured the worlds [as Trivikrama], O Tirumāl of fame beyond thought; at another time you dug up the earth [as the great boar]: so the sages say, and these are wonders. At another time you first churned the dark sea, and later [as Rāma] you dammed that same great ocean, O Lord whose body is like the great sea.