The first reference explains what this servant will not do and to whom:
Even a bruised reed he will not break;The second reference declares what he will do (or what Jehovah will do via him):
a dim wick he will not snuff out.
He will perform the work of justice
in the cause of truth. - Isaiah 42:3
... who dispatches chariots and horses,Some may think they have an idea who this servant might be. But as has been pointed out by others, it is not Christ Himself. Among the many other prophecies concerning this "one mighty and strong", he will have a clearly associated visual sign:
armies of men in full strength;
they lie down as one, to rise no more,
they flicker and die, snuffed out like a wick. - Isaiah 43:17
My servant, being astute, shall be highly exaltedThough Christ will heal him:
he shall become exceedingly eminent:
just as he appalled many—
his appearance was marred beyond human likeness,
his semblance unlike that of men—
So shall he yet astound many nations,
kings shutting their mouths at him—
what was not told them, they shall see;
what they had not heard, they shall consider. - Isaiah 52:13-15
But behold, the life of my servant shall be in my hand;Were this person to be aware of such a prophecy potentially referring to himself, he might be reluctant to have his appearance widely known.
therefore they shall not hurt him,
although he shall be marred because of them.
Yet I will heal him,
for I will show unto them
that my wisdom is greater than the cunning of the devil. - 3 Nephi 21:10