In plain words
The poet, of the fruit of this decad: Viṭṭucittaṉ, of ancient fame, adorned with valour [over the senses], who taught people to give only the sacred names of Māl [who loves his own], adorned with glory, set out this bright Tamil, a matchless jewel; those who master its nine and one will dwell for ever in Vaikuṇṭha of great beauty, cherishing him.