Who are the hypocrites?

Hypocrites are defined in the Qur’an as people who pretend to believe, when in fact they don’t, and who hope to take advantage of the believers among whom they live. Allah has informed us that hypocrites are corrupt people, who attempt to cause dissension among believers. In other words, they secretly aim to disturb the peace and harmony of believers. On account of this trait of theirs, they are described as “hypocrites” (munafiqun), meaning those who bring dissension and corruption (nifaq).

Another significant attribute of the hypocrites is that their real character only shows itself when the believers are facing difficulties, but at no other time do they reveal themselves. These people, who think that they are deceiving the believers are, in fact, themselves deceived. In the verse below Allah mentions the mistake that the hypocrites make:

Among the people there are some who say, “We believe in Allah and the Last Day”, when they are not believers. They think they deceive Allah and those who believe. They deceive no one but themselves but they are not aware of it. There is a sickness in their hearts and Allah has increased their sickness. They will have a painful punishment on account of their denial. (Surat al-Baqara, 8-10)

Allah has promised them the most painful punishment since they have demonstrated how vile they are. Out of arrogance and for the sake of some worldly benefit, they rejected faith after accepting it, even though full knowledge about religion and the Hereafter had been conveyed to them and even though they knew the messenger and lived together with believers. Their punishment is also because they attempted to cause dissension, were hostile to the messenger and to the believers, and provoked the unbelievers into acting against the believers:

The hypocrites are in the lowest level of the Fire. You will not find anyone to help them.  (Surat an-Nisa, 145)

Who are the hypocrites?