Read shakespeare's "sonnet lv"

sonnet lv
not marble nor the gilded monuments
of princes shall outlive this pow'rful rhyme;
but you shall shine more bright in these contents1
than unswept stone, besmear'd with [untidy] time.
when wasteful war shall statues overturn,
and broils2 root out the work of masonry,
nor mars3 his sword nor war's quick fire shall burn
the living record of your memory.
"gainst death and all-oblivious emnity4
shall you pace forth; your praise shall still find room
even in the eyes of all posterity5
that wear this world out to the ending doom.
so, till the judgment that yourself arise,
you live in this, and dwell in lovers' eyes.

—william shakespeare

1. these contents: the lines of this poem.
2. broils: quarrels, battles.
3. mars: god of war in roman mythology.
4. all-oblivious enmity: anything that would destroy your memory.
5. all posterity: the future.

what theme, commonly used by shakespeare, does "sonnet lv" illustrate?