First to start the main comparison between the two sonnets is the theme of love. In sonnet 55 Shakespeare describes a world of destruction and torment, yet the thoughts and memories of his love push him through and give him joy. In sonnet 43 Browning talks of the different types and feelings of love and she expresses them towards the reader. Shakespeare's sonnet is slightly darker and more apocalyptic then Browning's starts sweet and soft, then goes to stronger types of love, then in the end brings death and giving their entire life to the one they love. Browning's starts light and happy then ends with the ominous thought of death whereas Shakespeare starts dark and with death, then ends with the happy thought of his lover.
Browning throughout her whole poem uses repetition over and over in saying "I love". This puts emphasis on the overall theme of love and the author describing their love for another. The only time she talks of her love and does not use "I love" is when she talks about death near the turning point of the poem. Shakespeare however uses more imagery then repetition. In his sonnet during lines 1, 3, 4, 5, 6, and 7 Shakespeare uses imagery to paint a picture of a post or peri apocalyptic world. This helps shakespeare paint a picture of a destroyed and unforgiving world where he can paint the picture of his lover as brighter and more beautiful in comparison. This also helps with creating an image of what he would go through for his love.
The theme for both overall is love. In Browning's the theme could be people who love completely love with their entire life and more. In Shakespeare the theme could be people can be happy no matter what if they have true love.
I hope this is helpful to you.
