Jesus loves us so much that He doesn’t want any of us to leave Him. One of the major reasons that Jesus doesn’t want anyone to abandon Him (apostatize) is that it will cost them eternal life, which will take them to hell—a place of unending torment. He doesn’t want to lose us to that place.
A genuine believer will never fall away (John 10:27-30) but the ones who are not yet rooted in Christ, they are the ones who can fall away from the truth if they are not careful.
Many people who were followers of Jesus Christ started to abandon Him after hearing a hard teaching from Him that they misunderstood. This was that message:
53 So Jesus said to them, “I assure you: Unless you eat the flesh of the Son of Man and drink His blood, you do not have life in yourselves. 54 Anyone who eats My flesh and drinks My blood has eternal life, and I will raise him up on the last day, 55 because My flesh is real food and My blood is real drink. -John 6:53-55
To find the meaning on what Jesus said, you have to go a little down to verse 63 which says…
The Spirit is the One who gives life. The flesh doesn’t help at all. The words that I have spoken to you are spirit and are life. -John 6:63
The phrase “eat the flesh of the Son of Man and drink His blood” is a metaphor for accepting—when the time came—Jesus’ death for our sins and His resurrection by faith, acknowledging that He sacrificed His life for us—being punished on our behalf.
One of the reasons that people fall away and no longer follow Jesus—the Jesus that the Scriptures describes—is because they hit a wall (not knowing its true meaning), they will misunderstand a teaching in Scripture about a core doctrine and stumble over it. Because they misunderstood it, they will end up believing in a different Jesus, gospel, and spirit.
For if a person comes and preaches another Jesus, whom we did not preach, or you receive a different spirit, which you had not received, or a different gospel, which you had not accepted, you put up with it splendidly! -2 Corinthians 11:4
The Importance Of Prayer
Praying for understanding before reading the Scripture is essential. The Holy Spirit will reveal the meaning of the verses that you are reading and will guide you into its context to understand it properly, giving you insight. That is the only way that you can correctly apply God’s Word to your life.
If you come across someone who is teaching something strange, most likely, they are teaching false doctrine. You have to immerse yourself in God’s Word and study it to compare the teachings that’s out there so that you won’t get swept away.