Dawah is the act of delivering the message of God to people who are unaware or in a state of abandonment/rejection of God's Word.
Propagating the Good News is incumbent upon ALL Muslims, this of course is not a light business as salvation is on the line; thus Muslims should be as proactive as possible in the act of Dawah.
To alleviate/remove a common misconception it is important to note Muslims are NOT allowed to lie in order to gain converts, this is a malicious propaganda piece worked assiduously by people bent on sabotaging the effort of spreading the message of Abrahamic monotheism.
Here is a Muslim who has been preaching the Word to a Christian lady and due to God's Blessings, Love and Mercy this lady is closer to Islam, in this video you shall note the Muslim man is simply focussing on differences and similarities between her belief system and Islam in order to help her acquire the correct Aqida (belief system)
Of course the lady has a long way to go but this mode of intensive and broken-down (bite-size) Dawah is refreshing and well worth incorporating into one's own methodology of delivering the Truth to those who are willing to learn.
The Muslim gentleman makes sure the Christian lady is happy being recorded prior to the conversation, this is germane to some of the errors which are being made by fundamentalist "Christians" elsewhere.
The Muslim gentleman is sincere and acting out of LOVE, love and mutual understanding is far better than the abrasive approach some people take to evangelism
How does someone become a Muslim?
Simply by saying ‘there is no god worthy of worship besides God (Allah), and Muhammad is the Messenger of Allah. By this declaration the believer announces his or her faith in all God’s messengers, and the scriptures they brought.
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May Allah (God) bless the lady further and may Allah bless the Muslim gentleman further, Amen.