Sonnet LX

Like as the waves make towards the pebbled shore,
So do our minutes hasten to their end;
Each changing place with that which goes before,
In sequent toil all forwards do contend.
Nativity, once in the main of light,
Crawls to maturity, wherewith being crown'd,
Crooked eclipses 'gainst his glory fight,
And Time that gave doth now his gift confound.
Time doth transfix the flourish set on youth
And delves the parallels in beauty's brow,
Feeds on the rarities of nature's truth,
And nothing stands but for his scythe to mow:
   And yet to times in hope, my verse shall stand
   Praising thy worth, despite his cruel hand.

 The sonnet is a meditation on mortality. Almost as an afterthought the beloved is mentioned, in the final line, as one who might be preserved from the total oblivion of time's destruction. But despite its defiance, the closing couplet hardly rescues the reader from the thought that everything that is mortal must perish, for our minutes, and the minutes of our remembrance, move ever forward as irrevocably as the waves move forward, beating ceaselessly on the shore.

The sonnet seems to be placed deliberately at this point, as number 60, to coincide with the 60 minutes of the hour, just as No.12 marks the twelve hours of the day. There is even a pun included in line 2, (hour minutes) so that the reader need not lose his/her bearings in the sequence.

The 1609 Quarto Version

LIke as the waues make towards the pibled ſhore,
So do our minuites haſten to their end,
Each changing place with that which goes before,
In ſequent toile all forwards do contend.
Natiuity once in the maine of light,
Crawles to maturity,wherewith being crown'd,
Crooked eclipſes gainſt his glory fight,
And time that gaue,doth now his gift confound.
Time doth tranſfixe the floriſh ſet on youth,
And delues the paralels in beauties brow,
Feedes on the rarities of natures truth,
And nothing ſtands but for his ſiethe to mow.
   And yet to times in hope,my verſe ſhall ſtand
   Praiſing thy worth,diſpight his cruell hand.

Commentary

1. Like as the waves make towards the pebbled shore,
Like as In like manner to the way in which; make towards = proceed in the direction of (OED 35.b.) make as a verb of motion is not common, and perhaps derives form the word in combination, as below:

Make we our march towards Birnam. Mac.V.2.31.

It is still found in modern usage, as e.g. 'You make for the train while I make for the ticket office'.
pebbled - editors generally emend Q's pibled to pebbled. There were many old spellings for pebble, of which pible was one.

2. So do our minutes hasten to their end;
The imagery is of the disappearance and dissipation of each wave as it beats on the shore. The sea as such is not an obvious simile of human life, as it continues almost forever, whereas our life so patently has an ending. But the individual waves mimic the disappearance of the minutes. (See the comment on our minutes above in the Introductory note).
3. Each changing place with that which goes before,
Waves appear to change place with each other. As one rolls away, another takes its place.
4. In sequent toil all forwards do contend.
In sequent toil = in consecutive laborious procession. toil suggests exhausting labour, and perhaps the harshness of life's journey. The word toil is often connected with the strife of battle, (OED.n(1).1 & 2), and the idea is perhaps of the waves marching forward to contend, or fight, as lines of troops do in a battle.
5. Nativity, once in the main of light,
Nativity = birth. Here a new born child is implied, and nativity is abstract for concrete. Compare the similar use by Falstaff:

I hope good luck lies in odd numbers. Away I go. They say there is divinity in odd numbers, either in nativity, chance, or death. Away! MW.V.1.4-5.

the main of light - the full glare of light. the main refers to the sea, and being in the main implies being in the open sea. In the main of light is therefore 'in the open sea of light', 'where the light is most bright and unhindered'.

6. Crawls to maturity, wherewith being crown'd,
Crawls - as a baby crawls. Also suggestive of slowness, as the years of youth seem wonderfully long until they are gone. And in addition of the slowness and crabbedness of age.
wherewith
= with which i.e. maturity.
7. Crooked eclipses 'gainst his glory fight,
Crooked eclipses = malignant eclipses of sun or moon. Any heavenly eclipse was considered to be a dangerous event. Reversals of fortune could be attributed to their influence. eclipses therefore has a general meaning of 'blight caused by ill fortune', 'setbacks' etc. An eclipse may also be described in terms of the struggle of darkness against the light, as here, where the darkness fights against the glory of the sun, but figuratively against the glory of youth and maturity.
his glory
- his refers to nativity, maturity, youth, perfection.
8. And Time that gave doth now his gift confound.
his gift - Time's gift is presumably life itself, but all the accessories of life could be included, wealth, comfort, long age, posterity and so on.
confound
= destroy, overturn, . See 5, 8, 63, 64. The basic meaning is from Latin confundere - to pour together, to mingle things together in disorder. (OED 6) The general idea is that the elements that make up an individual are subsequently mingled together in the common mass.
9. Time doth transfix the flourish set on youth

As SB points out the meaning is fairly evident but explaining it is another matter. flourish may be taken as the 'heyday of perfection, the glory (of youth)', derived from the Latin verb florere, to bloom, to blossom, to be in one's prime. It is used in related meanings, frequently, for example, as a stage direction - Flourish of trumpets - meaning a fanfare of trumpets, or else simply as the single word Flourish. That is its most common use in Shakespeare. Here it suggests something like superlative appearance, supreme perfection, the ornament of youthfulness. There are no comparable uses elsewhere in Shakespeare. In
Good Lord Boyet, my beauty, though but mean,
Needs not the painted flourish of your praise
LLL.II.1.13-4.
and
Poor painted queen, vain flourish of my fortune!
R3.I.3.241.
'flourish' does not appear to have the same signification. Onions gives 'ostentatious embellishment, gloss, varnish', but those meanings are somewhat too harsh and pejorative to fit with ease here.

transfix usually means to run through, to pierce, as with a lance or sword, hence, by extension, to destroy. Time is the enemy which cuts down and destroys all things that are beautiful and transfixes them in perpetual rigor mortis.

10. And delves the parallels in beauty's brow,
delves the parallels = digs the furrows. parallels were defensive ditches often used in siege warfare. The imagery here, with the word delve, and mowing in line 12, seems more to refer to husbandry and the parallel lines drawn by the plough in the field., or by the spade, if ploughs were not used. These lines are compared to the wrinkles which line the forehead as 'beauty' grows older.
11. Feeds on the rarities of nature's truth,
the rarities of nature's truth - the image appears to be that of a beast or monster feeding on rare items. The presence of truth in the line and the difficulty of explaining the meaning of the phrase nature's truth may be partly due to the necessity of rhyme. truth always rhymes with youth in the Sonnets, whenever either word occurs at the end of the line. (6 times). Shakespeare does not use the phrase elsewhere, but I assume it is similar to the truth of honour in

....she, having the truth of honour in her, hath made him that gracious denial which he is most glad to receive. MM.III.1.162-4.

and it acts as an intensifier, as if it were 'pure, uncorrupted honour'. Thus nature's truth = nature itself, nature in its infinite expansion and perfection.

12. And nothing stands but for his scythe to mow:
stands = exists, grows (as in the phrase 'standing corn' for corn which has reached maturity).
his scythe
= Time's scythe. The scythe was used for mowing hay. Time and Death were frequently portrayed carrying a scythe. (See the woodcut engraving above).
13. And yet to times in hope, my verse shall stand
stand - see above. Also with the sense of 'stand up to', 'defy', since to times is to be taken with the verb. Thus 'my verse, as a beacon of hope, will stand against all consuming time, both now, and for all times in the future'.
14. Praising thy worth, despite his cruel hand.
thy worth - although the poem in a sense leads up to this, it is the only mention of the youth in the poem. the rarities of nature's truth and the flourish set on youth however may be taken as elliptical references to the beloved.
his cruel hand
- Time's cruel hand.