Richard Lynche was an English poet who lived from 1540-1610. He was a contemporary of Shakespeare, who lived from 1564 to 1614. Like Shakespeare, Lynche wrote many sonnets, which are 14-line poems that have a steady pattern of rhythm and rhyme.
Lynche's sonnet "What sugared terms" begins:
What sugared terms, what all-persuading art,
What sweet mellifluous words, what wounding looks
Love used for his admittance to my heart!
Such eloquence was never read in books.
The poet is describing how love entered his heart. It used "sugared" and "sweet" words to convince the poet to fall in love; it used a kind of eloquence (fancy, polished language) that is never even found in books.
The short answer to your question is that LOVE is being personified in these four lines. Although love is not a person, it is being described as a sweet-talking person who convinces the poet by using eloquent words.
Like many lovers, the narrative of this poem finds that love can be painful. In line 7, the poet states that love's pleasure has turned to pain, love's rest has turned to "trouble" and love's joy has turned to "annoy" (a nuisance).
The poem concludes:
Love looketh fair, but lovers are accurst.
A modern paraphrase would be: Love looks beautiful, but people who are in love are cursed.