Many of His disciples turned and walked away and did not follow Him anymore. Jesus asked the 12 disciples, "Do you also want to go away? Peter answered Him, "Lord, to whom shall we go? You have the words of eternal life." This did not mitigate their confusion but they knew in their hearts that they did not want to walk away. Jesus spoke figuratively and it confused even His closest disciples. But they did not walk away from Him.
Apostle John wrote, much later, that they went out from us, but they were not of us; for if they had been of us, they would have no doubt continued with us. When false believers walked away they revealed that they did not belong to the Christian community. They were never true believers in the first place.
Jesus said to His disciples, "You did not choose Me, but I chose and appointed you." He also prayed over the twelve saying, "Those whom You gave Me I have kept, and none of them is lost except the son of perdition, that the Scripture might be fulfilled." So even though the disciples were very confused at times, they were being spiritually kept and could not turn their backs on the Lord.
I also experienced this when I up and decided to break up with the Lord because we could not see eye to eye. I got down on my knees to pray my good-bye prayer, and when I had said all I wanted to say, I got up to walk away and collapsed back down on my knees in a heap of wailing as never before seen. I could not do it, in the same way that Jesus's disciples were being kept, I couldn't walk away from Eternal Life.
As Christians, we are indwelt with the Holy Spirit. This impartation is called anointing. It joins us to the Anointed One and we share in His anointing.
There are those falsely professing Christ that don't share in His anointing. Of these people in the last day Jesus will say to them, "I never knew you. Depart from Me."
But of those who ate of His flesh and drank of His blood, they will have everlasting life, just as He said. We are kept by the power of His anointing. Jesus said, "My sheep hear My voice and I know them, and they follow Me. And I give them eternal life, and they shall never perish, neither shall anyone snatch them out of My hand. My Father, who has given them to Me, is greater than all; and no one is able to snatch them out of My Father's hand."
But of those who ate of His flesh and drank of His blood, they will have everlasting life, just as He said. We are kept by the power of His anointing. Jesus said, "My sheep hear My voice and I know them, and they follow Me. And I give them eternal life, and they shall never perish, neither shall anyone snatch them out of My hand. My Father, who has given them to Me, is greater than all; and no one is able to snatch them out of My Father's hand."
Blessed assurance, Jesus is mine
O what a foretaste of glory divine
Heir of salvation, purchase of God
Born of His Spirit, washed in His blood
Perfect submission, all is at rest
I in my Savior am happy and blessed
Watching and waiting, looking above
Filled with His goodness, lost in His love
This is my story, this is my song
Praising my Savior all the day long
This is my story, this is my song
Praising my Savior all the day long
Blessed Assurance by Third Day