What's difficult is that with the gospels and the epistles, we get what his disciples taught and believed along with what Paul taught.
Here's a link to a site that looks at what
Jesus taught...
The two greatest commandments, according to Jesus, are to “love the Lord your God with all your heart and with all your soul and with all your mind” and to “love your neighbor as yourself”
But that's straight out of the Jewish Bible...
Leviticus 19:18 Do not seek revenge or bear a grudge against anyone among your people, but love your neighbor as yourself. I am the LORD.
Deuteronomy 6:5 Love the Lord your God with all your heart and with all your soul and with all your strength.
Then it talks about God's Kingdom...
A major theme in Jesus’ teaching was the Kingdom of God or Kingdom of Heaven. This refers to God’s spiritual reign and authority over the lives of people who trust and obey Him...
According to Jesus, the Kingdom will be established fully when He returns to judge the world and abolish evil forever (Matthew 13:24-30, 36-43). Jesus used parables to illustrate how the Kingdom grows and what it will be like.
I hope all this judgement stuff is wrong. But, if not, then there's going to be a lot of people cast into hell. Unless you don't believe that Jesus really taught those things. And, since this is a thread by a Baha'is, their prophet didn't abolish evil, and they don't believe in a literal hell or a literal Satan.
Then a big one, repentance and forgiveness of sin...
Jesus repeatedly called people to repent, warning about the consequences of unrepentant sin (Luke 13:1-5). To repent means to turn away from sin, wrongdoing, and selfishness and to submit our lives to God. Jesus linking repentance with entering the Kingdom of God (Matthew 4:17).
Through His death on the cross, Jesus opened the way for people to be made right with God, forgiven of sins, and granted eternal life (John 3:16-17).
We access this forgiveness and life by turning to Jesus in repentant faith (Acts 3:19).
So, did Jesus teach this, or was it his disciples? Either way, who loves God with all their heart? And who loves their neighbor as themselves? And, other than some Christians, who believes that only those that believe in Jesus, like those Christians say you have to, will be saved? And everybody else will be cast into hell.
I don't know if we can really separate out what Jesus taught and what the NT says. They're sort of claiming that what they say is what Jesus taught. And I chose not to believe it.
But I do see the value of trying to live by the "Golden Rule" and do unto others like you'd want them to do unto you. But I don't practice it perfectly.