This is going to be quite an expository read for you folks, so bear with me.
There are a lot of verses thrown around for and against Eternal Security. A lot of them make sense when read alone. A lot of them make sense when read in context. So, if there are many good points for both side, one would have to analyze every single reference of Scripture that is in favor of Conditional Security and Eternal Security to come up with a legitimate conclusion... or he could find at least one reference of Scripture that explicitly states whether one can lose his salvation or not. That's what I've intended to do here. So I have one question:
What does the Bible say about Eternal Security?
John 6:35-40 says,
"35 Jesus said to them, "I am the bread of life; whoever comes to me shall not hunger and whoever believes in me shall never thirst. 36 All that the Father gives me will come to me, and whoever comes to me I will never cast out. 37 For i have come down from heaven, not to do my own will but the will of him who sent me. 39 And this is the will of him who sent me, that I should lose nothing of all that he has given me, but raise it up on the last day. 40 For this is the will of my Father, that everyone who looks on the Son and believes in him should have eternal life, and I will raise him up on the last day." (ESV)
Here is one of seven "I AM" claims of Jesus recorded in this Gospel. There are also several absolute statements where Jesus refers to himself as "I AM," in keeping with the reference to God as "I AM" in Exodus and Isaiah. Jesus as the bread of life nourishes people spiritually and satisfies the deep spiritual longings of their souls. In this sense, those who trust in him shall not hunger; that is to say that their spiritual longings to know God will be satisfied (corresponding with what John Piper claims in his book Desiring God). Verse 37 states that whoever comes to Jesus will never be cast out. This implies that people should never think that they have not been chosen by God. Jesus promises to receive everyone who comes to him [alone] and trusts in him [alone] for salvation. Yet, in verse 44, Jesus states the almost paradoxical statement that only those who are called by the father may come to Jesus. It is only until the Holy Spirit reveals to them that they realize that behind their willing decision to come and believe lies the mysterious, invisible work of the Father who was all along drawing them to Christ.
My Bible footnotes that this corresponds with Romans 9:1-23 and Ephesians 1:3-6. Then in verse 39, Jesus says, "this is the will of him who sent me, that I should lose nothing of all that he has given me, but will raise it up on the last day." I think that this implies two things: that everyone who has been chosen by the Father has been "given" by and from the Father to the Son for salvation will indeed(!) be saved. In verse 40, Jesus further explains that these people whom the Father has "given" to him will believe and have eternal life. This last verse is, I believe, the nail in the coffin of Conditional Security, or the idea that one can lose their salvation. This final verse in this passage explicitly says that it is God's decreed will that everyone who believes in Christ will attain eternal life, and will be raised up on the last day. The implications are that one must truly believe to attain salvation and that those who believe for a time or only appear as if they believe will not attain salvation. So then, here it has become not a question of whether or not one can lose his salvation anymore. It has become a question of who is actually saved, or, on an even deeper level, who truly believes.
John 10 concurs much with the previous passage, and I would hope so because it's in the same Gospel!
John 10:26-29 says,
"26 but you do not believe because you are not among my sheep. 26 My sheep hear my voice, and I know them, and they follow me. 28 I give them eternal life, and they will never perish, and no one will snatch them out of my hand. 29 My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father's hand." (ESV)
This passage says that those who belong to Jesus' flock (i.e., those who are chosen by him) are those who believe or will believe. The reason people do not believe is because they are not a part of his flock, which implies that God must first give them the ability to believe and make them part of his people with a new heart. Eternal life by its very definition cannot be taken away, especially when Jesus' sheep belong to him and his Father. Then in verses 28 and 29, his sheep are given utter assurance of their salvation. He says no one can snatch them out of his hand (contrast with Romans 8:38-39). This should be our assurance. There's nothing that can snatch us away from Christ.
And finally in 1 John 2:19, it says,
"19 They went out from us, but they were not of us; for if they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us." (ESV)
This verse is in reference to John's readers seeing people who had recently left the church. Although they were outwardly part of the church, their departure revealed that they were not truly ever part of it ("not of us"). (See also Luke 8: 4-15.) It says that if they were truly "of us" they would have stayed, they would have persevered. This implies those who are truly "of us," or truly of Christ's fold, or truly saved will never abandon Christ. We are kept by his grace (Romans 6:1, Jude 24). And finally the phrase, "that it might become plain" again reveals God's sovereignty in all situations and choices, and the divine plan that he has for everything, even the departure of this group.
There are a multiplicity of other verses and passages that confirm this, but only one is truly needed. I hope I cleared things up if anyone was struggling with this or confirmed what some people were suspicious of or wondering about.
Until next time,