The teachings of Jesus are simple. But Christian religions that try to interpret the 'entire Bible' and 'follow it completely' get easily confused about what's required for everlasting life.
Confusion is why we have so many different religions today. Each one has different ideas about what is right and wrong. There is much disagreement as to what true Christianity is even though the answer is very simple. Everyone has valid opinions but no one can prove they are 'the only true religion'. 
The Watchtower admits that mistakes are possible. Christians who follow the entire Bible can make claims and quote Bible scriptures, but no one can prove that their understanding of the Bible is superior to someone else's interpretation.
True Christians do not follow Jehovah, the God of the ancient Israelites, the Apostles or the saints or the bishops or the early Christian congregation. True Christians follow Jesus. He is their only authority. Matthew 28: 18,19.
That's why true Christians do not need to study the 'entire Bible'. Also some scriptures contradict the teachings of Christ. True Christians rely only on the words of Jesus. True Christians believe that Jesus alone is their savior. Therefore only the teachings of Jesus are needed to be saved. If Jesus didn't say it, it's logically not required for 'everlasting life'. See All Scriptures Are Inspired
The message of Jesus is simple. No other doctrines and beliefs are not required for salvation. Jesus is the only path to 'everlasting life' That's why true Christians follow what Jesus said and no one else.
True christians are 'like minded' and united in the teachings of Jesus. They are not confused about 'the truth' because the truth is simple. The entire message of Jesus is easy to understand.
Yes. Christians are free to believe whatever they want in addition to the words of Jesus, however the definition of 'true' Christianity is following Jesus Christ and him alone.
Therefore true Christians do not judge other Christians harshly for celebrating holidays, shopping at the Salvation Army, having a blood transfusion, being a member of the YMCA, attending the church of their choice, and other things Jehovah's Witnesses can't do. All these 'extra' beliefs Jesus didn't teach should be a matter of conscience and not a requirement for true Christians. Luke 6:37
True Christians also read an unbiased translation of the Bible. (The New World Translation has been altered to fit the doctrines of Jehovah's Witnesses and contains many serious errors. )
We recommend any good 'study' Bible with the words of Jesus highlighted in red. Some translations are written in plain English. These are jam packed with references and facts you will not find in the New World Translation. The best study Bibles are reasonably priced from $30 - $50.
It's important to read what Jesus really said without 'coloring' his words with your current beliefs. In other words if you had no religious opinions whatsoever and were reading the words of Jesus for the very first time, how would you interpret his message?
Also consider the time period in which the scriptures were written. It's important to read the words of Jesus with an open mind and heart.
The underlying message of Jesus was simple and very easy to understand. Jesus taught true Christians unconditional love for neighbors and 'enemies'. Jesus said his followers should love the ungrateful and the wicked like God does. Luke 6:35. Jesus even forgave his executioners as he died a painful and disgraceful death.
1. Who has the only true religion? The answer will surprise you. What Can Rainbows Teach Us About Religion?