Protestant by Convection or Convenience
Are you a protestant by conviction or convenience? If you believe that Roman Catholics are Christian too then it is by convenience rather than conviction that you are a protestant. I dearly love Roman Catholics but hate Catholicism. How can I say that I love Roman Catholics but hate Catholicism? It is because I love Roman Catholics that I hate Catholicism.
Catholicism keeps Roman Catholics from being justified in the sight of God. Catholicism teaches that salvation comes through baptism, through the keeping of commandments (CCC 2068), through confession to a priest followed by penance, and through sacraments all of which must be done in the Catholic church.
The bible in complete contrast to this teaches that all have sinned and fall short of the glory of God (you can't keep the commandments). That we are justified by God (not a priest) as a gift (not baptism) by His grace (not penance) through faith (not sacraments) in Jesus alone (not the church). (see Romans.3.23-26).
Jesus said to Martha; "I am the resurrection and the life; he who believes in Me will live even if he dies, and everyone who lives and believes in Me will never die. Do you believe this?" (Jo.11.25-26). Twice in that statement Jesus uses the word believe. The bible was not originally written in the English language, the New Testament was written in Greek, so often times we can gain more understanding by studying the original language. The English word BELIEVE in that passage is translated in scripture, into English from the Greek word πιστεύω (PISTEUŌ); which means to entrust. This is more than a simple acknowledgement of the truth, it is an implicit trusting. So the question isn't do you believe in Jesus (who He is) while that is an imperative, because you must believe in Jesus before you can believe Jesus. The question is do you believe Jesus (trusting in Him alone for salvation)?
Catholicism teaches much about Jesus that is true. In fact I can't think of anything at the moment about the Lord Himself that Catholicism teaches that is not true. Therefore, Roman Catholics do believe in Jesus (who He is), that He is the Christ the only begotten Son of God, but that is not the problem. The problem is this; while Roman Catholics do believe who Jesus is they don't believe Jesus Himself, because Catholicism teaches one to trust the church and his own works for salvation.
"I am the resurrection and the life; he who believes in Me will live even if he dies, and everyone who lives and believes in Me will never die. Do you believe this?" (Jo.11.25-26). If you do not believe this what you must do is repent. The English word REPENT is translated in scripture, into English from the Greek word μετανοέω (METANOEŌ); which means to change one's mind. Jesus said to Nicodemus, "Most assuredly, I say to you, unless one is born again, he cannot see the kingdom of God." (John.3.3). Change your mind and come follow Jesus; He is the Christ the only begotten Son of God, and has promised eternal life to everyone who believes in Him. "The time is fulfilled and the kingdom of God is at hand, repent and believe in the gospel." (Mark.1.15).
New American Standard Bible. (1995). The Lockman Foundation.
For more information on the difference between Protestant Christianity and Catholicism click on this article by Matt Slick: What is the difference between Protestantism and Catholicism?