It is important to take the whole Bible in context and interpret scripture with scripture. If there is no warning to the believer about securing his/her salvation, then it is a question not necessary to even be answered. I do believe the Bible does teaches a secure salvation, but not eternal security for a person's salvation. What I mean by this is that a person must continue to trust in the salvation provided by Jesus Christ. It is not unconditional, just as 1 John 1:9 is conditional. Sin is only forgiven if it is confessed-"IF we confess our sins, He is faithful and just to forgive us our sins and cleanse us from all unrighteousness." IF is the key word of this verse-IF is a condition, not unconditional. Salvation only comes through Christ and Him alone, all other efforts are in vain and will result in being lost (Romans 8 and Galatians 4-5). Calvin taught that Jesus only died for the elect (limited atonement)which totally goes against the Word of God. Salvation is made available to anyone who would receive the gift purchased by Christ. Yes, God will in His foreknowledge know who will accept or reject His offer, but I do not believe God controls the choice. God does not reveal Himself as a Father who waves a gift or present in front of all humanity and tease them with salvation, only to pull it back and say, "Sorry you were not chosen, you were not one of my elect, go to hell!" Whosoever(John 3:16) means just that, anyone can come to Christ. Anyone can receive the gift of salvation. Just as you can receive a gift, you can also reject it. To say that someone never received a gift is not logical. I might receive a gift in the mail and open it up. You can not tell me I did not receive the gift. At the same time, I can wrap up that gift and send it back, not accepting it. God will not force us to serve Him, He does not want robots! He longs for our fellowship with Him and that was purchased and restored by Jesus Christ. Many believers have rejected Jesus after they opened the gift which was free to any who wanted it. If you want to accept eternal security, then you must accept all four other points of Calvinism to make it work. Too many people who accept one or two points of Calvin's teachings do not understand they all are connected together-you can not seperate them. You must take them all or reject them all. It is much like constructing a tall building. You can't build all the stores of the building except the 3rd or 4th stores, the building will collapse. Calvin and others that followed him in his teaching taught five points. 1) Total Depravity of Man-man can not come to God, God must go to him. 2) Unmerited Favor-Grace was extended to you without any choice-you can not reject this grace. 3) Limited Atonement of Jesus Christ-Jesus only died for the "elect" and them only, all other people not chosen are predestined to be damned to hell without any choice. 4) Irresistable Grace-once God chose you to be "elect" you are elect no matter what-meaning you had no chose in the matter-God predestined you to be saved no matter who or what you did. 5) Perseverance of the Saints (Eternal Security)-you are chosen or "elect" you have no say or can not be unelected. God already chose you to be saved. (This is why if you truly believed this, we need to stop preaching the Gospel to everyone and lie to multiple millions upon millions that Jesus died for them and their sins. If they are truly elect, God will make a way for them to be saved! This is so unbiblical it makes my heart just break thinking about it!). God died for all and some will receive this and others will reject. Others will accept and continue to serve God and enter into the rich reward promised to them. I hope this is clear as I have tried to explain in just a few lines the truth I believe the Bible holds. Remember, only one interpretation is correct! One is right and the other is wrong. I am siding with the whole Bible and not picking out just a scripture here and there to support a false doctrine like Calvin's.
