You need to understand the Protestant Mindset™ before undertaking any apologetics with a Protestant. The Protestant Mindset™ consists of two factors in equal quantities:
- Sola Scriptura
- Ritual is evilThose two factors drive everything they know and believe about God, and everything they *think * they know and *do * believe about Catholics. They believe that Catholicism is not biblical, and they believe that everything we do is ritualistic.
You could attack those beliefs and prove them wrong. But you won’t win any souls for Christ.
Rather than attack those beliefs, play into them. Protestants are unimpressed by most Catholics because most Catholics don’t know their Bible. In order to get to their hearts you must do so through the only means they trust - The Bible. Read it. Know it. Be able to quote scripture and verse. When they say “you are justified by faith alone” be prepared to quote James 2:20 - “Faith without works is dead.” The Bible is their shield. You must get inside that shield, and the only way to do it is to know that book.
You will have to debunk their prejudices. When they ask you why you call priests “father,” you will have an answer ready. When they ask you why you pray to statues, you better be able to tell them why you do not. When they ask you why you worship Mary, you better have that answer on your lips.
You will find that when you are face-to-face with evangelicals, they’ll change topics on you very quickly to a) throw you off; and b) prove their biblical knowledge/superiority. You should be up to the task. Don’t let them change the topic. Explore each one until they either agree with you or stump you, in which case it’s time to get back to the books.
Going at the task half-hearted will only make them more secure in their prejudices, and you may do more harm then good. If you are not up to the task, don’t try it.
Also, it’s a good idea (on several levels) to pray with them. Lead them in prayer to the Lord, and trust the Lord to fill their hearts with his law.
Most of all, pray that the Holy Spirit fills you with the knowledge and the courage to face the most difficult challenges. Pray that he gives you the words and the conviction to approach the challenge both as a humble disciple of Christ, and with the revolutionary zeal of recent convert to Christ.
Peace, and pleasant evangelization everyone!