"Wherefore the rather, brethren, give diligence to make your calling and election sure: for if ye do these things, ye shall never fail." (2 Peter 1:10) The thought of losing one's salvation is a scary one. A thought that must be acknowledged and worked through at some point in our life and walk. Peter talks before the above verse about how everything has been laid out for us and he says "for if ye do these things..."
You can never be too sure
"What things?" (Luke 24:19)
"If ye know these things, happy are ye if ye do them." (John 13:17)
Jesus in both the above verses referencing (in the top) all His activity prior to His crucifixion and also His example of servanthood to the disciples. I should say the latter will segue into the former. But before it does, we have to realize we are "dead indeed unto sin but alive unto God through Jesus Christ our Lord." (Romans 6:11) Along with this realization goes (as in, leaves) the thought that you will never lose your salvation. But what about...? I find the morbid introspection of the thinker in ferreting out the way of life leading up to one's ultimate neglect of "the Lord that bought them" (2 Peter 2:1) is pointless and fruitless. Firstly, if you're concerned about losing your new life in Christ, it's a good sign. Secondly, if someone chooses to ignore God all the livelong day, the question arises whether or not they were ever "bought" in the first place.
"Set your affection on things above, not on things on the earth. For ye are dead, and your life is hid with Christ in God." (Colossians 3:3)
The part of you that lived and walked around before you accepted Christ is long gone. This is true. This is gospel. It's on the books and it's in God's heart. You've made a connection and the room's been filled. Now, the hard work of reorienting your thinking to be in line with His as He leads you from this life to the next is where the struggle begins and continues.
The killer
Because that's what we come up against time and again. Dying to our own will. The phrase may sound odd in light of modern parlance, but it means something. It means that the very road we don't want to go down, the one that seems to be a dead end but that you know God is calling you to, is what we choose. We do it for Him.
In closing, there's a word: catalepsis. It holds a couple meanings. One of them comes to us from psychiatry and it's pretty serious. It essentially refers to showing no response to any stimulation and even to the point of looking, for all intents and purposes, like one is dead. The other definition has to do with insects literally playing dead in order to escape any predators. As Christians, we can either respond to God or not respond at all...