A group of Shia Muslims requested Imam Sadeq (AS) to advise them. Imam (AS) said:

Irecommend you Divine Piety and obedience of Allah (SWT) as well as avoiding sins; and I suggest that you become a silent preacher. They asked: How can we invite the people to you in silence? Imam (AS) replied: Interact with people by friendship, justice, and trust. If the people do not see anything from you except good deeds, just by looking at you will say: May God bless their Imam who educated such companions [1].

[1] Da’aa’emul Islam, Vol. 1, Page 55.

Source: en.shafaqna.com