- The early sonnets, written when Shakespeare was in his early 20s, celebrate the beauty and virtue of a young man, traditionally identified as Henry Wriothesley, 3rd Earl of Southampton. Shakespeare expresses his love for the young man in passionate and sensual terms, praising his physical beauty, his intelligence, and his kindness.
- As the sonnets progress, Shakespeare's tone becomes more complex and ambivalent. He begins to express doubts about the young man's fidelity and to worry about the destructive power of time. He also starts to explore the darker side of love, including jealousy, possessiveness, and anger.
- In the later sonnets, Shakespeare shifts his focus from the young man to himself. He reflects on his own aging and mortality, and he expresses his fear of being forgotten. He also writes about the power of poetry to immortalize beauty and love.
The sonnets end with a powerful affirmation of the power of love to transcend time and death. Shakespeare writes, "Love's not Time's fool, though rosy lips and cheeks / Within his bending sickle's compass come." This suggests that love is stronger than time and that it can endure even after death.