Allah is perfect and has made everything perfect. All the worlds including Earth and the humans on it are perfect. Everything happens according To His Will.
Why? Because he loves us.
According to hadith:(All is well with the believers under all circumstances"
It reminds us that in the divine Knowledge All is well, all is complete)
But you have to see it that way. It is about perception. It is a spiritual thing. You have to have faith for your own good.
Abu Yahya Suhaib bin Sinan (May Allah be pleased with him) reported that:
The Messenger of Allah (ﷺ) said, "How wonderful is the case of a believer; there is good for him in everything and this applies only to a believer. If prosperity attends him, he expresses gratitude to Allah and that is good for him; and if adversity befalls him, he endures it patiently and that is better for him".
I am going to try to explain it.
For example, if a person had been healthy instead of having to stay home and rest, that person might have been run over by a car and killed. So who is to say that being perfectly healthy is better? In fact, perhaps one’s illness or other disability has somehow kept you alive. ( source: http://drlwilson.com/articles/PERFECT.htm) I just used the example.
Another example:
Maulana Jalaluddeen Rumi (Rahmatullah ’alaih) narrates a story in
his Mathnavi; an incident which occurred during the time of
Rasulullah e: Once, after having performed wudhu, Rasulullah e
was about to wear his leather sock when an eagle came along,
snatched it and flew away. Nabi e was most distressed as he was
preparing for Salaah.
In a short while, the eagle returned and turned the sock upside down,
towards the ground, causing a snake that was inside, to fall out.
The eagle then presented the sock to Rasulullah e and addressed him
: “O Rasulullah e ! The reason for me having taken the sock was that
there was a snake hidden inside it. Otherwise I would never harm you,
for Allah Ta’ala has ordered me to protect you. It was on account of
the snake that I flew off with the sock.”
So for a believer everything is always for his own good.
Answer this question as Einstein said (but smart he didn't answer it you have to answer it for yourself) Is the Universe Friendly? Replace Universe with Allah
If you say no then you will see this world as hostile and see behind every human and three enemy and this will cause you stress and anger and enmity. This will effect your thinking, behavior toward others.
But if you say yes then you will see friends everywhere. Remember God has provided the sun for you, the air the trees and the people to help you develop spiritually learn lessen and test. If you become ill and you Thank Allah for the illness because you know it is for your own will( may be you have to learn something or experience something whatever the reason is it is good)
Another example. If you have a cut and you say stop the bleeding I don't want to bleed because it is bad and evil. Then how will you be healed? The blood comes and becomes hard so that a new skin develops and then when the skin is developed you scratch the hard blood of because it itches and voila! you got a new skin.
If you go to a doctor and he gives you an injection(vaccine) to heal. But if you say No I don't want an injection the doctor is evil he wants to hurt me then how will you be healed. So you have to ACCEPT the injection and TRUST the doctor in order to be healed
TRUST = TAWAKKUL and ACCEPT= DESTINY(Always for your own good)
But you will not always understand or see the reason because you are not God. But thorugh Divines Eye everything is perfect. You just have to see it that way.
And if you see that God is always is with you and never leaves you. (In your everyday lives and experiences) then you will be automatic grateful and praise with your heart Allah! I felt that way when I saw it that way I felt whole, connected to the world and protected everywhere even dark in the night in the woods if I wanted to go there.
The consequence is that your thinking (VERY IMPORTANT!) and your behavior towards other will be friendly, because you know that Allah helped you so much!) Even when someone hurts you. You will Thank Allah for this hurt because it is for a good reason for you but you don't know And maybe you can give love back to that person( for example thank him) This way you will not feel hate or want to hurt them back!
Another consequence is that you don't become cynical(VERY IMPORTANT!) to this world and stay uplifted and happy.
Another consequence is that your heart will feel at peace. You know that you are at the perfect place and the perfect time and your feelings are perfect at the moment. Then you will not doubt yourself and and love yourself. But in a humble way. Every mistake that you made unintentionally(sometimes intentionally) you know it is Divine will, so it is perfect. You will not feel hatred to yourself
What is good what is evil? All is perfect!(praise to Allah) An accident is perfect death is perfect maybe if someone lived longer he wold indulge in sins. (Allah knows) (don't say this cynical but really try to see it that way with love)
Satan works for Allah for your own sake. If you have Tawakkul he will go away!
But don't think I am perfect, because you are not. (if you understand what I mean)
Remember live is about love (Allah loves you so much that you don't even know that).