John 15:4 "Remain in me, and I will remain in you. For a branch cannot produce fruit if it is severed from the vine, and you cannot be fruitful apart from me."
When I read this verse, the word that jumps out at me is remain. Jesus said that in order for Him to remain in us, we must remain in Him. I know there are different understandings of what this is saying, but taken at face value the message seems to be very clear. We must remain in Christ.
Why would Jesus command us to remain in Him if there wasn't a possibility that we might now? Staying in Christ is a decision we must make daily in our lives. We must knowingly choose to live in relationship with Him. We must strive to live lives that are pleasing to Him. We must understand that apart from Him we are spiritually dead. We cannot remain in fellowship with Him on our own. Without a heart connection with Christ we will stumble and fall into sin.
Apart from Christ, we cannot produce anything good; we cannot do anything that is pleasing and acceptable to God. Apart from Christ, we will produce no spiritual fruit. Period. We will produce fruit if we are living in Christ and if we aren't living in Christ we will be rejected by God.
In order for us to remain in Christ, we must feed our souls consistently with the Word of God and spend time alone with Him in prayer. We must be worshipers of Him and we must be servants of Him. We must strive to apply to our living what we learn from Him. We must desire Him more than anything else in our lives.