One of the central themes in Shakespeare's "Sonnet 116" is the idea of love as a constant force that cannot waver. The poem also stresses that love is invaluable and challenges the idea that love can wane over time.
Shakespeare's "Sonnet 116" is one of 154 poems that the poet wrote in Shakespearean sonnet style. Each poem consists of 14 lines following an "a-b-a-b, c-d-c-d, e-f-e-f, g-g" rhyming pattern. Most of Shakespeare's sonnets explore themes of love. "Sonnet 116" centers on the meaning of true love.
One of the more important themes in "Sonnet 116" is the concept that "Love alters not." It is an everlasting force that cannot wear down when it faces challenges or wane over time. Shakespeare uses many metaphors containing natural imagery to make his point; for example, he claims that love is "an ever-fixed mark,/That looks on tempests and is never shaken." He repeats similar words to stress that love is not truly love when it does not last: "love is not love/Which alters when it alteration finds,/Or bends with the remover to remove."
Shakespeare also presents love as something that is invaluable: "It is the star to every wand'ring bark,/Whose worth's unknown, although his height be taken." One can know that love is an important force, but cannot ever conceive its true value.
Shakespeare emphasizes his theme of love as a constant by challenging the concept that love can break down over time. He writes that "Love is not Time's fool," and that it "alters not with his brief hours and weeks,/But bears it out even to the edge of doom."