Leaders of the movement held official positions as preachers in the major mosques of Baghdad and Istanbul, and "combined popular followings with support from within the Ottoman state apparatus".
As the movement progressed, activists became "increasingly violent" and Kadızadelis were known to enter "mosques, tekkes and Ottoman coffeehouses in order to mete out punishments to those contravening their version of orthodoxy.
It is in Istanbul where he engaged in a career as a mosque preacher, through "the path of sermon and admonition,"[5] conversely he eventually neglected the prudish teachings of his Balıkesir guides.
The debate that Kadızade and Sivasi stirred in Istanbul during their lifetimes continued to spill over to other Ottoman cities and to subsequent generations long after the original antagonists were dead.
[7]Kadizade in his sermons "used the grand pupil of Aya Sofya to propagate a kind of fundamentalist ethic, a set of doctrinal positions intended to rid Islam of beliefs and practices that had accumulated since the era of the Prophet Muhammad’s Medina.
In addition, the Kadızadeli movement specified precise Koran sanctions against wine and had sermons paying attention to a variety of controversies that had progressed during the Prophet Muhammad era.
"[8] According to the Sufi spokesmen, and others opposed to the Kadızadeli movement, contends that “Kadızadeli-labeled "innovation" was either not canonically forbidden or had flourished for centuries within the community and thus stood validated by the principle of consensus.”[8] According to Mustapha Sheikh, under the leadership of Uṣṭūwanī, attacks on un-Islamic behaviour were not left to the authorities.
As the movement progressed, activists became "increasingly violent" and Kadızadelis were known to enter "mosques, tekkes and coffeehouses in order to mete out punishments to those contravening their version of orthodoxy.
In addition, "other damning usages, according to Kadızadelis, included pilgrimages to the tombs of alleged saints; invocations of blessings upon the Prophet and his Companions upon each mention of their names; collective supererogatory prayers and rituals of post-patriarchal origins; the vilification of the Umayyad Caliph Yazid; the use of bribery among officeholders; and grasping hands and bowing down before social superiors" According to Kadızadelis, those who rejected to abandon such innovations were "heretics who must reaffirm their faith or be punished".
[8] The Kadızadelis promoted their ideals in the mosques "for public support of an activist, interventionist, 'enjoining of right and wrong', and demanded of their congregations not only that they purify their own lives, but that they seek out sinners and in effect force them back onto the straight path".
Kadizadeli scholars, such as Kadızade Mehmed (d. 1635), were known for their strict interpretation of Islamic texts and their opposition to practices they deemed innovations (bid'ah), such as Sufi rituals, the veneration of saints, and the use of coffee and tobacco.
Similarly, Muhammad ibn Abd al-Wahhab advocated for the purification of Islam from what he considered corrupting influences, including certain Sufi practices and popular religious customs.
While there is no direct evidence of a lineal connection between the two movements, the similarities in their reformist agendas and their shared emphasis on scriptural literalism have led to speculation about a possible ideological kinship.
Many academics and scholars have argued that the Kadizadelis were self-serving and hypocritical; since most of their criticisms were based on the fact that they were on the fringes of society and felt alienated from the rest of the social order.