When engaging in dialogue with Christians, a good portion of your time may be simply spent on dispelling myths, misconceptions, and straw man arguments about not only Islam, but also about Christianity itself. Most laypeople in the world are generally uninformed about religion in general, including their own.
I will say that non-Protestants (IE Catholics, Arab Christians, and Eastern Orthodox) tend to be easier to talk to and more open minded. Protestants tend to have more problematic views about both Christianity and their view of other religions. A main reason behind this is the more “structured” denominations offer a clear creed and theology, whereas Protestantism really has no clear theology or creed, as it splits up into a whole bunch of different opinions and denominations.
Here’s two common misconceptions I hear from Christians:
#1: “I Already Know That I’m Going to Heaven”
This is very common among Christians, especially when attempting to challenge Muslims who believe they will not know their destination until after death. The reality is that even in Christian theology, Catholicism delineates that are mortal sins and venial sins. Mortal sins can lead to damnation if a person does not repent of the sin before death. This is similar to Islam (though not exactly) in some respects.
Christians also tend to misunderstand Islam as believing that Muslims enter heaven via good deeds. Yet we have a clear hadith saying that nobody enters Heaven except by Allah’s ﷻ Divine grace and mercy, not even the prophet Muhammad ﷺ himself.
Granted, Protestants are all over the place on this one, and generally tend to believe that all sin is equal, “once saved always saved,” and other problematic theological views that aren’t very well thought out. They’ll typically turn to accusing people of “not being Christians,” so excommunicating people on a whim becomes a thing. For example they’ll accuse an apostate (like a Muslim convert) of having “never been a true Christian.” Exactly how they define this is up to random whims and off the cuff interpretations of the Bible which go off in all directions. They have no clear creed and Martin Luther’s writings themselves seem confused.
In Islam, we are between being assured of salvation and despairing of Allah’s ﷻ mercy (per aqida Tahawiyah). We do good deeds to earn a higher place in Heaven, strengthen our iman (faith), draw nearer to our Lord, and seek His pleasure and mercy.
#2: “My Sins Are Already Forgiven, I Don’t Need to Ask for Forgiveness”
This ties into #1. This ignores the concept of contrition/attrition and repentance, which is all over the New Testament, especially in Luke 15 where three parables are presented about repentance and salvation. The first two parables end with very pertinent statements:
I tell you that in the same way there will be more rejoicing in heaven over one sinner who repents than over ninety-nine righteous persons who do not need to repent. (Luke 15:7)
In the same way, I tell you, there is rejoicing in the presence of the angels of God over one sinner who repents. (Luke 15:10)
Repentance is not just a part of Catholicism, either. It’s also important for salvation in Protestantism, though there are varying opinions and common misconceptions about it among them. Protestants are supposed to be constantly repenting, as are Catholics and all other Christians, and Muslims as well! Even Martin Luther’s first point of his 95 Theses espouses this:
When our Lord and Master Jesus Christ said, “Repent” (Mt 4:17), he willed the entire life of believers to be one of repentance.Martin Luther’s 95 Theses
Similarities and Differences
Now here’s where a parallel forms between Islam and Christianity. Both assert that people should regularly repent. Both Catholicism and Islam assert that mortal sins must be repented for to be forgiven. And both Christianity and Islam generally assert that good deeds alone do not enter one into heaven–faith is necessary to enter through God’s grace. Though they disagree on the details and articles of faith, and consider one another disbelievers. Muslims consider disbelieving in the prophet Muhammad ﷺ to be disbelief, and associating partners with God (like the Trinity) to be the worst sin.
Christians mostly believe that Muslims do not believe in the divinity of Jesus ﷺ and thus are not believers in vicarious redemption, so they are not befitting of Heaven and the Kingdom of God. Though after the second Vatican Council, the pope declared that Islam can lead to Heaven. Protestants generally affirm that Muslims are all going to Hell forever, and we Muslims affirm that any disbeliever in the last and final prophet ﷺ is going to Hell forever. In Islam, a Muslim may go to Hell (IE for living a sinful life that is not forgiven), but all Muslims will eventually be taken out and entered into Heaven. In Christianity, Hell is eternal for everybody who enters.
These types of arrogant, armchair pundit comments typically reinforce the Muslim’s conviction in the truth of Islam and the great clarity that it brings. The whimsical approach to the Bible and to theology that is observed among Christians nowadays brings a certain appreciation for Islamic creed.