Jesus makes it very clear, there is no way to half heartedly follow Him. Either we are with Him or against Him. Either we confess our faith in Him or deny Him. When we confess our faith publicly in Jesus, He will tell God the Father that we are one of His followers. If we deny Jesus, He will deny us. We don't want that to happen.
The Holy Spirit is the one who leads us to faith, gives us faith and keeps us in the faith. The sin against the Spirit is saying "No" to the Spirit so many times we cannot say yes.
"Who is Jesus?" is the most important question we all have to answer.