In plain words
The poet, of Kaṇṭam: He spread out and rose up [measuring the worlds] until he reached them, his form the colour of a sapphire, and the moon, whose body holds water, and the hot sun, whose great rays spit fire, both took fright: the home of Māl, Puruṣōttama, is the eminent city called Kaṇṭam, on the Gaṅgā, made bright by waters that flow down mingling the koṉṟai flowers from the crown of the one whose matted locks shine with good [Śiva, who bears the river] and the tulasi from the feet of Nārāyaṇa.