How to respond to criticism?

Imagine, Allah (swt) talks to you directly. He sends Quran to one among you. He (swt) is in direct conversation with one among our people. He even leads us to a victory through Angels in Badr and leads us to better understanding of Him in Uhud. Like He is always there approachable, available and sending down His message. If we want to follow people who are on right track, we can not find people better then those who were in direct contact with Him (swt) through Prophet Muhammad (saw). That time dictates:-

Should we kill the blasphemous 1400 years ahead in future.

Should we place the insulter of our Prophet (PBUH) in solitary confinements.

Should we kick the guy who incites us by burning Quran.

So these people are in direct contact with heavens above. Not only muslims. Jews and christians a like. They get live instructions. Quran being a live book, does not fade over time. Those instructions synced with the events happened then are still telling us to stick to following principles:-

1. Forgive people who harm you vocally and even physically.

2. Wait for the death, we will get everything we have sent forward to Him (swt).

3. Say your prayer and give zakat, because no better way exists to avoid calamity then to embrace it.

4. It is purely Allah's jurisdiction. He gives Hell to people by His choice. He gives Heaven to people by His choice. Iblees does ibadah for entirety and ends up becoming the biggest enemy of Allah (swt). So arguing over which sect is better and which is wrong, is stupid.

Embrace the calamity, Ayat 110 - 112

Next big thing talked in these verses is to embrace the Calamity. You might lose in Uhud (Ayat 109), you might get ridiculed for the purest love you give to people around you. You let them enter your homes, You even give them protection from their enemies. But they mock you and ask you questions like:-

"O Muhammad! Turn al-Safa into gold, expand for us the land of Mecca and make rivers gush out throughout it — if you do this, we will believe in you!"

"Bring us an entire book from heaven as did Moses bring the Torah."

"Bring us a book from heaven which reads; This is from the Lord of the Worlds to Ibn Abi Umayyah; know that I have sent Muhammad to mankind."

"We shall not believe in you until you bring the angels as guarantors."

Link to reference.

So what you do after all this humiliation?

You forgive them. You say your prayer. You pay zakat. Because this religion is a religion of peace. It does not tell you to put these people in Solitary confinements. And when you listen to Allah (swt), as in Ayat 112, you will not have any fear of them nor sadness will get to you. In short, a tip to living a fearless and happy life is to stay calm, peaceful and let go of the dirt thrown at you. Focus on your goals.