We rest our hopes on you to be bearers of a message calling people there to your religion, principles and values. Do not underestimate your worth, and you should be discouraged from doing so, for the great religion of Islam has spread in many areas of the planet through merchants who travelled from Muslim lands or immigrants who sought refuge in these lands which were not subject to any military or Islamic invasion.
Also, the sect of followers of Ahl al-Bayt (the best of peace and blessings with them) has spread in most areas of the earth through this way without the backing of military might. Rather, it was carried to these lands by travelling incomers, and their residents accepted it from them due to the strength of its argument and clarity of its evidences, and because it combines logic with passion; so, prepare yourself to carry the message in the same manner and to work hard at it.
Let your call be first and foremost by your good manners, gentleness, good conduct, attractive companionship among those with whom you now live. Try to introduce them to one thing after another in a gentle and kind way, and take them out of their inattention through wisdom and beautiful exhortation, hopefully Allah Almighty will guide through you His servants and save them from the Fire.
In the reliable narration of al-Sukuni, Imam al-Sadiq (peace be upon him) quotes the Commander of the Faithful (peace be upon him) saying, "The Messenger of Allah (peace be upon him and his progeny) dispatched me to Yemen. He said to me, 'O Ali! Do not fight anyone before inviting him to accept Islam. By Allah, if Allah, the most Exalted One, the most Great, leads one person through you to guidance, it is better for you than everything on which the sun shines and sets."[i]
In a tradition narrated by Hammad, the latter reported: I said to Imam Abu Abdullah [Al-Sadiq] (peace be upon him): "I visit the lands of polytheism, and there are among us those who say that if I die, I will be gathered [on Judgment Day] with them.” The Imam (peace be upon him) said to me, "Oh Hammad, when you were over there, did you express our message and invite others to our creed?” I answered in the affirmative. The Imam (peace be upon him) further asked me: "When you are in these cities, the cities of Islam, do you do the same?” I answered in the negative. The Imam (peace be upon him) then said to me, "If you were to die over there [in the cities of polytheism], you would be resurrected as a nation all by yourselves, and your radiant light will run ahead of you.”
Within your religious occasions and celebrations and creed-relevant rituals there is great advantage and support for all this, as we stated in the eighth chapter :
"(As for) those who strive in Our (cause), We will certainly guide them to Our paths, for truly Allah is with those who do right” (Qur'an, 29:69).
[i]Wasaail Al-Shi'a, Vol. 11, p. 30.