Hypocrite is the word generally used to translate the Koranic term munafiqun, the active participle of the third form of the root n-f-q. Its verbal noun, nifaq is usually translated as hypocrisy. The etymology of nifaq and munafiqun is disputed, but they are often associated with the nouns nafaq means tunnel, and nufaqa and nafiqa i.e. the burrow of a rat or a jerboa. The connotation of hiding underground and undermining is very apt, since this is precisely what the munafiqun are accused of. Another view suggests that the original meaning of the term munafiq was the one obliged to pay the nafaqa, a kind of tax exacted from all members of the ummah in Medina, including the Jews, at the time of war. Those who were reluctant to pay the nafaqa came to be regarded as uncommitted to the cause and hence as hypocrites. The Koran also mentions another minor form of hypocrisy, called riya or alternatively ri'a, which connotes an ostentatious display of piety (2:264, 4:38, 8:47). The concepts of nifaq and munafiq (un) as well as various verbal forms of n-f-q are mentioned in thirty Koranic verses, such as 3:167; 4:61, 88, 138, 140, 142, 145; 6:35; 8:49; 9:64, 67, 68, 73, 77, 97, 101; 29:11; 33:1, 12, 24, 48, 60, 73; 48:6; 57:13; 59:11; 63:1, 7, 8; 66:9. The 63rd Koranic chapter is also entitled Sura al-Munafiqun. The insincere and doubtful believers are frequently discussed without explicit use of this terminology. The hypocrites are considered half-hearted believers, who outwardly profess Islam, while their hearts harbour doubt or even unbelief.
The munafiqun (hypocrites) are identified as the Muslims opponents of the Prophet in Medina, who half-heartedly accepted him and his message and did so for worldly gain and in order to safeguard their position in the community, which they would otherwise have lost. When their expectations were not met, they turned against the Prophet. The Koran does not mention any names, but a long list of the hypocrites and their Jewish patrons and allies may be found in the biography of the Prophet, vide Ibn Ishaq's Sira (pp. 351-63). The undisputed leader of the dissenters is identified as Abdullah bin Ubayy bin Salul, whose political ambitions were thwarted by the arrival of the Prophet in Medina. He also sided with the Jews of Medina and the Meccan opponents. He promised to come to the aid of the Jews of Nadir if the Muslims were to confront them, but he subsequently abandoned them in their hour of need.
The hypocrites are described in the Koran as follows: they are not sincere (2:8-16), not to be taken as friends (4:144), refusing to fight (3:166-7, 4:77-80), their false oaths (9:62, 74), not accepting Prophet's judgment (4:60-64; 24:47-50), secret counsels of (4:81-2, 114), acting as spies (5:41), spread false reports (4:83), practice deception (4:142-3), their mocking (9:65), effort to destroy Muslims (4:113), seeking friendship with enemies of Islam (5:52), their opposition to Prophet doomed to failure (4:115), enjoying evil and forbidding good (9:67), building mosque to sow dissension among Muslims and affording shelter to enemies of Islam (9:107-110), etc.