Sura 111-- This is a judgment on an enemy of the Quran. It isn't really that different-- and certainly no worse-- than the curses in the Psalms (see 109:6-20!) or the curses of the prophets. We don't know why this man was so cursed, but that is often the case in ancient poetry.
Sura 87-- This has some basics of the Quran. God is a God of order, not chaos. What God wants of us is to live according to His Path. This Path is not complicated, but easy to follow. This Path is revealed, bit by bit, in the process of revealing the Quran. Those who oppose the path will be destroyed on the day of judgment. Note that this is really no different than a good portion of Jesus' claim. He said that the "gospel" or his teaching was essential for entering the kingdom and those who lived it would live and those who didn't would be judged (see Matthew 7:21-27).
In seeing these claims from different people, we need to ask these questions:
a. Are these claims contradictory? In other words, is it possible to follow both sets of teachings?
b. Which one, if either is speaking for God? How could we know if one is or is not?
Surah 92-- Again, a summary of The Path:
So he who gives (in charity) and fears ((Allah)),
And (in all sincerity) testifies to the best,-
We will indeed make smooth for him the path to Bliss.
And gives the lie to the best,-But he who is a greedy miser and thinks himself self-sufficient,
We will indeed make smooth for him the path to Misery;
Nor will his wealth profit him when he falls headlong (into the Pit).
Is this really different from Jesus' teaching? Jesus said:
Beware, and be on your guard against every form of greed; for not even when one has an abundance does his life consist of his possessions.
The land of a rich man was very productive.
And he began reasoning to himself, saying, 'What shall I do, since I have no place to store my crops?'
Then he said, 'This is what I will do: I will tear down my barns and build larger ones, and there I will store all my grain and my goods.
And I will say to my soul, "Soul, you have many goods laid up for many years to come; take your ease, eat, drink and be merry."'
But God said to him, 'You fool! This very night your soul is required of you; and now who will own what you have prepared?'
So is the man who stores up treasure for himself, and is not rich toward God."
And He said to His disciples, "For this reason I say to you, do not worry about your life, as to what you will eat; nor for your body, as to what you will put on.
For life is more than food, and the body more than clothing.
Consider the ravens, for they neither sow nor reap; they have no storeroom nor barn, and yet God feeds them; how much more valuable you are than the birds!
And which of you by worrying can add a single hour to his life's span?
If then you cannot do even a very little thing, why do you worry about other matters?
Consider the lilies, how they grow: they neither toil nor spin; but I tell you, not even Solomon in all his glory clothed himself like one of these.
But if God so clothes the grass in the field, which is alive today and tomorrow is thrown into the furnace, how much more will He clothe you? You men of little faith!
And do not seek what you will eat and what you will drink, and do not keep worrying.
For all these things the nations of the world eagerly seek; but your Father knows that you need these things.
But seek His kingdom, and these things will be added to you.
Do not be afraid, little flock, for your Father has chosen gladly to give you the kingdom.
Sell your possessions and give to charity; make yourselves money belts which do not wear out, an unfailing treasure in heaven, where no thief comes near nor moth destroys.
For where your treasure is, there your heart will be also.
Both are basically saying: Have faith in God and don't be greedy. Jesus' teaching perhaps applies more broadly than most of us are comfortable with (as he paints a businessman as being judged and he says "sell your possessions and give to the poor"), but are not Muhammad and Jesus saying basically the same thing?