Ecclesiastes 12.1-7

The penultimate section of Ecclesiastes is also the third poem of the book, and with a very similar structure.

1.3-11	3.1-9(-15)	12.1-7
Question	Statement	Statement
5 examples	14 pairs of examples	5 examples
Statement	Question & conclusion	Conclusion

The biggest question surrounding this section is the way to read it. If one were to read it literally, then it might well be describing the scene of a town perhaps in the aftermath of a plague. Many have died, this is yet another funeral procession, those looking on know their death is also nigh - the signs are there. 

Another way to look at it is to see past the literal to the metaphorical and ask: what do these signs represent? As such, what we see in 12.1-7 is the description of the effects of old age on the body. This follows on from the discussion in 11.7-10 highlighting the good of youth, yet always with reference to old age being ominously near. 

a Statement about the Creator when death is near (12.1)
  b when the eyes fail (12.2)
     c when the face degrades (12.3)
        d when the hearing stops working (12.4)
     c' when the stomach degrades (12.5)
  b' when the frame fails (12.6)
a' Conclusion about God when death has come (12.7)

To be clear, the language of this section is quite difficult, with words appearing here and here only in the whole Bible, and there are some questions remaining, but overall this appears to be the flow. 

For structure's sake, I would've loved to see verse 2 in the centre of the structure, as sight has been so pivotal to Qohelet's observation throughout, but to frustrate me (pun intended) he leaves it as the first example of the failing body. Qohelet may also be drawing on a Sumerian proverb quoted in Bendt Alster, Studies in Sumerian Proverbs (1975), quoted in Roland E. Murphy, Ecclesiastes, Word Biblical Commentary (1992):

My grain roasting fails,

Now my youthful vigor, strength and personal god

have left my loins like an exhausted ass.

My black mountain has produced white gypsum.

My mother has brought in a man from the forest;

he gave me captivity.

My mongoose which used to eat strong smelling things

does not stretch its neck towards beer and butter.

My urine used to flow in a strong torrent.

but now you flee from my wind.

My child whom I used to feed with butter and milk,

I can no more support it.

And I have had to sell my little slave girl;

an evil demon makes me sick.

The Sumerian poem obviously uses different images although there are many similarities, in particular the happy conflation of the literal and metaphorical. 

To conclude, when we note that our poem is bookended with references to God, this is an exhortation to direct our attention to him while we still can. There will be the day (should we live long enough) when our faculties will fail us. Until that day comes we must make every effort to know God and to live the life he has given us to live. For the day will come when joys will be taken, faculties will be taken, and ultimately even our spirit will leave our bodies when the decay has taken over.