The morals and qualities necessary for a Da`y (caller to Islam) are highlighted by Allah (Glorified and Exalted be He) in many occurrences in the Qur'an.
First: devotedness. It is obligatory on a Da`y to be so devoted to Allah that he neither intends to show off, nor wants a good reputation nor praise from people. Rather, he should only call to Allah to please Him.
Say (O Muhammad ﺻﻠﻰ ﺍﷲ ﻋﻠﻴﻪ ﻭ ﺳﻠﻢ): "This is my way; I invite unto Allâh (i.e. to the Oneness of Allâh Islâmic Monotheism)
And who is better in speech than he who [says: "My Lord is Allâh (believes in His Oneness)
Therefore, you have to be devoted to Allah (Glorified and Exalted be He). It is the most important virtue and the greatest quality that has to characterize your way of Da`wah (call to Islam), i.e. observing Allah and the Hereafter.
Second: knowledge. Invite people to Allah with firm knowledge. You should not be unaware of or ignorant about what you call people to.
Say (O Muhammad ﺻﻠﻰ ﺍﷲ ﻋﻠﻴﻪ ﻭ ﺳﻠﻢ): "This is my way; I invite unto Allâh (i.e. to the Oneness of Allâh Islâmic Monotheism) with sure knowledge
Knowledge is an inevitable obligation. You should not call people while you are ignorant nor talk about a topic you are unaware of. An ignorant person destroys and never constructs, spoils and never reforms. You, servants of Allah, have to fear Allah and never say anything about Him without knowledge. Likewise, you should never preach something unless you have sure knowledge and insight into what Allah and His Messenger (peace be upon him) said about it. Sure knowledge is inevitable and essential for a seeker of knowledge or a Da`y to be fully conversant with and have a deep knowledge of all the aspects of what he calls to. He must also be sure of the proofs that substantiate his topic. Once he is sure of the truth of his point, he should then call people to it, regardless of whether it is a call to do or to abandon something, i.e. an act of obedience to Allah and His Messenger or an act forbidden by Allah and His Messenger (peace be upon him). The call should be based on sure knowledge and insight.
Third: among the qualifications necessary for a Da`y is that he should have patience, kindness and softheartedness with forbearing temperament as the prophets (peace be upon them) were. Never should a Da`y be rushing, violent or unduly strict. Rather, he has to be patient, forbearing and kind while practicing Da`wah.
Invite (mankind, O Muhammad ﺻﻠﻰ ﺍﷲ ﻋﻠﻴﻪ ﻭ ﺳﻠﻢ) to the Way of your Lord (i.e. Islâm) with wisdom (i.e. with the Divine Revelation and the Qur'ân) and fair preaching, and argue with them in a way that is better.
And by the Mercy of Allâh, you dealt with them gently.
"And speak to him mildly, perhaps he may accept admonition or fear (Allâh)."
O Allah, who (happens to) acquire some kind of control over the affairs of my people and is kind to them, be kind to him; and who (happens to) acquire some kind of control over the affairs of my people and is hard upon them, be hard upon him.
So, it is obligatory upon you, slaves of Allah, to be kind in your Da`wah, and not to be harsh with people. Do not make people turn away from religion because of your harshness, ignorance or violent, harmful approach. It is thus obligatory on you to be forbearer, gentle and pleasant and lenient in speech so that your words may have an effect on the heart of your brother, or that it may have an effect on one toward whom your Da`wah is directed. As such, people will receive your Da`wah better, will be affected with it and will show appreciation. On the contrary, harshness causes disaffection, distance, and division, not unity.
Among the necessary etiquettes and attributes a Da`y should, or even must have is to act upon what he is calling people to. He should be a good example for those whom he invites to Allah that is, he should not call to something which he himself does not do, or call to abandon something that he himself does. In fact, this is the condition of the losers we seek Allah's refuge from this. But the winning believers call to the truth, act upon it, practicing it actively and vividly and never do what they forbid people to do.
O you who believe! Why do you say that which you do not do? Most hateful it is with
Allâh that you say that which you do not do.
Enjoin you A lBirr (piety and righteousness and each and every act of obedience to Allâh) on the people and you forget (to practise it) yourselves, while you recite the Scripture [the Taurât (Torah)]! Have you then no sense?
On the Day of Resurrection, a man will be brought and thrown in HellFire. His intestines will then pour forth and he will revolve around them like a donkey revolves around a millstone. The people of Hell would gather around him and say: "O, so and so, what happened to you? Did you not use to command us to adhere to right and forbid us to do wrong?" He will say: "Of course, it was so; but I used to enjoin right but did not practise it myself and I used to forbid wrong but committed it."
This will be the case with whoever calls to Allah, enjoins good and prohibits evil while his words are contrary to his actions we seek Allah's refuge from this.
So, from among the most important and greatest attributes a Da`y has to be characterized with is to act upon that which he calls people to and not to do things that he prohibits. A Da`y should have excellent behavior, good reputation, patience, persistence, sincerity and strife in guiding people to goodness and keeping them away from falsehood. He should supplicate to Allah to guide the people whom he invites. He should say to the people he invites: May Allah guide you, grant you the ability to accept the truth. Thus, you should call and guide him, forbear his misbehavior and even supplicate to Allah to guide him.
O Allah, guide Daws and bring them close.
So, you should supplicate to Allah for those you call to be guided and accept the truth with patience and persistence and do not lose hope. Moreover, you should say only that which is good and never rebuke or say bad words that might cause people to turn away from truth. However, if someone commits aggression and injustice, they will be given different treatment.
And argue not with the people of the Scripture (Jews and Christians), unless it be in (a way) that is better (with good words and in good manner, inviting them to Islâmic Monotheism with His Verses), except with such of them as do wrong
So, the one who commits injustice through opposing the Da`wah with evil and enmity is to be dealt with in a different manner. If possible, such a person should be imprisoned or given suchlike disciplinary punishment, which depends on the kind of injustice he commits. But as long as he causes no harm, you should be patient,
seeking Allah's reward, and to argue with him in ways that are best. Anyway, if such a person causes you any personal harm, it is to be endured with patience as did Allah's messengers and those who followed them in good.
I ask Allah (Glorified and Exalted be He) to grant us all the ability to practice Da`wah in the best manner. May He reform our hearts and actions and grant us understanding of and holding fast to the religion. May Allah also make us among those who are guided, who guide others, are righteous and teach others righteousness. Surely He (Glorified and Exalted be He) is the most Supreme, the Most Noble. May Allah's peace and blessings be upon His Slave, Messenger and Prophet Muhammad, his family, Companions and all those who followed in good till the Day of Judgment.