It must be emphasized that there is a right and wrong way to go about engaging with non-Jews, from the most benign and inquisitive non-Jews to the most aggressive missionaries. Keep a smile on your face; stay friendly and engaged, and fashion your rebuttals in the form of questions or gentle reminders. Adopt the attitude that you are trying to convert these missionaries to Judaism! Remember that our non-Jewish friends almost always have sincere and noble intentions, however misguided. Make it your goal to shepherd them, be a beacon of light to them, as they emerge from the darkness of their unwitting idolatry. It can only be with love that we will conquer hearts!
If the conversation turns ugly or unpleasant, if antisemitic themes are raised, don't respond with anger or venom. Understand where it is coming from. In most cases, it is a sign of the desperation and fear that people naturally have when their deep-seated beliefs are suddenly imperiled. In a few cases, it is a polemic strategy used to bait us into speaking or acting in disparaging ways or distracting and getting us off track from an otherwise solid line of argumentation. Either way, the correct response is to smile, rise above the conversation, and point out that such talk is contrary to the word of God and unbecoming of a believer in God. Ask if these anti-Jewish ideas are sourced from God or from men claiming to speak on behalf of God.
If the acrimony from our non-Jewish friends becomes unavoidable, then very gently and lovingly remove yourself from the conversation, being the adult in the room, and inform them you will resume the conversation when they can speak with love and not hate in their hearts. In most cases, after a time has passed, they will reach out to you and apologize for their misbehavior.
That being said, winning over a non-Jewish friend requires much more than just the right attitude. Winning over a heart also requires winning over a mind. Equip yourself and your loved ones with knowledge. Have a weekly bible (Tanakh) study. If that sounds icky or foreign to you, it shouldn't. Jews invented the art of Bible study!😺 Once you become more conversant with scripture, you will happily discover that the snippets from the Tanakh (the "Old Testament"), which our non-Jewish friends use to underwrite their beliefs (and challenge ours), are typically, actually saying precisely the opposite of what our Christian friends have been taught. Once the context and correct translations have been restored, the words formerly used against us are transformed into powerful instruments of proof of and defense for Judaism! Winning over a non-Jewish friend is usually as easy as saying: "Let's go look at that section of the Bible and see what God is really saying, shall we?"
As will be explained in a future post, Christianity and Islam have only ever viewed Judaism through pagan conceptual schemes and (often deliberate) mistranslations. Restoration of the correct reading of scripture goes a considerable distance towards the conclusive end of a dispute.
In fact, most missionaries will simply abandon any further attempt to proselytize to you once they see you know the original Hebrew meaning of scripture. They will go off in search of easier prey. However, you ought not let them go! You ought to seek to cure their disease and not just treat a symptom.
Conduct yourself with tenderness and compassion, for we are helping to bring those lost in the shadows back out into the clear daylight of truth, a process which can be frightening and painful at first. If the other person simply can't have a friendly, open discussion, then tell them: "Perhaps, we can continue at a later time." Whatever happens, always maintain your dignity and virtue. I can't emphasize this enough.