The Muslim Should Use Soft Words

Every Muslim has the duty to call others to the morality of Islam, to inform them of the existence of God and the proofs of His creation. God Himself has revealed that responsibility in Verse 3: 104: "Let there be a community among you who call to the good, and enjoin the right, and forbid the wrong. They are the ones who have success." He also reveals how that invitation is to be made:

Call [them] to the way of your Lord with wisdom and fair admonition, and argue with them in the kindest way. Your Lord knows best who is misguided from His way, and He knows best who are guided. (16:125)

Correct and courteous words accompanied by forgiveness are better than charity followed by insulting words. God is Rich Beyond Need, All-Forbearing. (2:263)

True believers know the importance of this responsibility, described in Verse 3:114: "They believe in God and the Last Day, and enjoin the right and forbid the wrong, and compete in doing good. They are among the righteous." Therefore, they call on all those around them--friends, relatives, everyone they can reach--to believe in God, fear Him, and display a proper morality. This pleasing characteristic of Muslims is described in Verse 9:71:

The men and women of the believers are friends of one another. They command what is right and forbid what is wrong, and perform prayer and pay charity tax, and obey God and His Messenger. They are the people on whom God will have mercy. God is Almighty, All-Wise.

From this verse, it's clear that all believers, throughout the course of their lives, are charged with explaining that proper morality, living by it themselves, recommending good deeds to others and advising them to avoid evil. God commands believers to use soft words, "Say to My servants that they should only say the best…" (17:53)

God describes good words and bad in this analogy in the Qur'an (14:24-27):

Do you do not see how God makes a metaphor of a good word: a good tree whose roots are firm and whose branches are in heaven? It bears fruit regularly by its Lord's permission. God makes metaphors for people so that hopefully they will be reminded. The metaphor of a corrupt word is that of a rotten tree, uprooted on the surface of the earth. It has no staying-power. God makes those who believe firm with the Firm Word in the life of this world and the hereafter. But God misguides the wrongdoers. God does whatever He wills.

Anyone who wishes to lead a virtuous life should encourage others toward virtue. Anyone who wants to see good should make an effort to help spread it. Anyone who wants to see others behave according to their conscience should encourage them to do so, and anyone who opposes cruelty should warn those who engage in it. In short, anyone who wants right to prevail should call on all others to abide by it. When issuing that call, however, it's most important to keep in mind that only God can inspire people to become Muslims, and cause words pleasing to them to have any effect. God has revealed that our Prophet (may God bless him and grant him peace), as a result of his noble character and superior morality, always treated people well--and has recommended him as a role model for all mankind.