[In the talk “Need for Tablīgh”, Maulāna Ashraf ῾Ali Thānvi rehmatullāhi ῾alayh says]
Sahābah had undertaken numerous sacrifices for the propagation of Islām. Today we are wiping away those sacrifices through our heedlessness. Some non-Muslims claim that Islām was spread through the sword, and now it is our time (and we are in power), so we are using the same might.
However, this is absolutely incorrect because the use of sword was for the defense and protection of Islam (and its values) rather than its propagation. Maulāna Qāsim Nanotvi rehmahullah answers this allegation very beautifully. He says that if Islām was spread through the sword, then there has to be swordsmen to yield those swords. So which sword was used to gather those swordsmen who later used swords to spread Islām?
In reality, Islam’s propagation has been done through the morals and character of Rasulullah salallahu ῾alayhi wasallam and Sahāba radiallahu anhum. The books of history and Sīrah testify this fact. If we too bring those morals and characters into our lives, then non-Muslims will accept Islām merely by looking at us. But alas, our characters have depleted to such a level of decadence that non-Muslims use it as an evidence to instill hatred.
Someone had said to a non-Muslim, “Become Muslim”.
He replied, “I cannot become a Muslim of the caliber of Bāyazīd1, because I am unable to do so. And as for becoming a Muslim like you, I would not like that for myself. I am better non-Muslim then that.”
Khutbāt Hakīmul Ummat, vol. 13, pg. 304
1. Bāyazīd Taifūr ibn `isā al-Bistāmi rehmatullah ῾alayh (d.261H) was a great sūfi saint from Persia. More on his life can be read from Here