"In Sonnet 116, Shakespeare considers time as the great adversary to love." Elucidate.
The quote you have given could actually be used as the basis to discuss a number of Shakespeare's sonnets, which seem to place the passing of time in conflict with the beauty of the object of the speaker's affections and their love. However, famously, this poem seems to capture this conflict in its evocation of what "true love" should be in a relationship, pointing towards an eternal, unchanging sense of love that remains constant in spite of whatever damage time may do. Consider what love is said not to be, and then what it is said to be:
Love is not love
Which alters when it alteration finds,
Or bends with the remover to remove:
O no! it is an ever-fixed mark
That looks on tempests and is never shaken;
Love is therefore described as unchanging and not impacted by the changing landscape around it wrought by time. In particular, love is said not to be "Time's fool," even though beauty obviously comes under the power of time in the way that it fades so fast. Even though beauty and physical appearance may change thanks to the power of time, true love remains unchanged in the face of such decay:
Love alters not with his brief hours and weeks,
But bears it out even to the edge of doom.
Note the way in which these lines place love in direct conflict with time, in the form of "brief hours and weeks." Thus, although this sonnet clearly places love and time in conflict, it is obvious that true love is never seriously threatened by the power of time, because true love is eternal and will carry on "even to the edge of doom." Whilst time has power over our appearance and age, true love renders such transformations as meaningless.