The motive of amorous passion, for instance, was a very divining-rod in his hands, revealing the most delicate relations between Nature and the soul.  Ibykos had pointed the contrast between the gay spring time and his own unhappy heart in which Eros raged like ’the Thracian blast.’  Theocritus had painted the pretty shepherdess drawing all Nature under the spell of her charms; Akontios (Kallimachos) had declared that if trees felt the pangs and longings of love, they would lose their leaves; all such ideas, modern in their way, had been expressed in antiquity.

This is Shakespeare’s treatment of them: 

  How like a winter hath my absence been
  From thee, the pleasure of the fleeting year! 
  What freezings have I felt, what dark days seen! 
  What old December’s bareness everywhere! 
  And yet this time removed was summer time,
  The teeming autumn, big with rich increase ... 
  For summer and his pleasures wait on thee. 
  And thou away the very birds are mute,
  Or, if they sing, ’tis with so dull a cheer
  That leaves look pale, dreading the winter’s near,
                                             (Sonnet 97.)

  From you have I been absent in the spring,
  When proud-pied April dress’d in all his trim
  Hath put a spirit of youth in everything,
  That heavy Saturn laugh’d and leap’d with him. 
  Yet nor the lays of birds nor the sweet smell
  Of different flowers in odour and in hue
  Could make me any summer’s story tell.... 
  Yet seem’d it winter still.... (Sonnet 98.)

Or compare again the cypresses in Theocritus sole witnesses of secret love; or Walther’s

  One little birdie who never will tell,

with

  These blue-veined violets whereon we lean
  Never can blab, nor know not what we mean.
                              (Venus and Adonis.)

Comparisons of ladies’ lips to roses, and hands to lilies, are common with the old poets.  How much more modern is: 

The forward violet thus did I chide;
Sweet thief, whence didst thou steal thy sweet that smells
If not from my love’s breath?... 
The lily I condemned for thy hand,
And buds of marjoram had stolen thy hair;
The roses fearfully on thorns did stand,
One blushing shame, another white despair.... 
More flowers I noted, yet I none could see
But sweet or colour it had stolen from thee. 

          
                                                                        (Sonnet 99.)

And how fine the personification in Sonnet 33: 

Full many a glorious morning have I seen
Flatter the mountain tops with sovereign eye,
Kissing with golden face the meadows green,
Gilding pale streams with heavenly alchemy;
Anon permit the basest clouds to ride
With ugly rack on his celestial face,
And from the forlorn world his visage hide,
Stealing unseen to West with this disgrace: 
Even so my sun one early morn did shine
With all triumphant splendour on my brow;
But out, alack! he was but one hour mine;
The region cloud hath mask’d him from me now. 
Yet him for this my love no whit disdaineth;
Suns of the world may stain when heaven’s sun staineth.