Ali 'Imran 3:20

Fa-in hajjooka faqul aslamtu wajhiyalillahi wamani ittabaAAani waqul lillatheena ootooalkitaba walommiyyeena aaslamtum fa-inaslamoo faqadi ihtadaw wa-in tawallaw fa-innama AAalaykaalbalaghu wallahu baseerun bilAAibad

So if they argue with you, say, "I have submitted myself to Allāh [in Islām], and [so have] those who follow me." And say to those who were given the Scripture and [to] the unlearned, "Have you submitted yourselves?" And if they submit [in Islām], they are rightly guided; but if they turn away - then upon you is only the [duty of] notification. And Allāh is Seeing of [His] servants.

Then, if they argue with you, say: “I have submitted myself to Allah, and (so did) those who have followed me.” And say to those who have been given the Book, and to the unlettered: “Do you submit?” If they submit, they will be on the right path. Yet, if they turn back, then you have only to convey the message. Allah is watchful over (all of) His servants.