But let's examine "he falls away" used in this parable. What would you say they are falling away from?
Here is something I just thought of, when I read your question.
We also read in the Bible about how there will be "a great falling away" before the man of evil is revealed, if I remember correctly. And I thought of how if you have a city with great walls, there is the straight and narrow way who is Jesus, to enter the city properly and you can become a citizen.
But there can be the many dishonest, dishonorable people who are trying to climb ladders all around that city, to sneak and force their way over the wall, into the city. But there are soldiers and citizens who are pushing all those ladders off the wall, so there is a great falling away of all those ungodly ones who are on those ladders.
They try to climb their way up the steps of the ladders, then they get too high and they fall backward >
"God resists the proud" (in James 4:6, 1 Peter 5:5) so they can not get things their own way. They believe in the city, but they do not do what they need to do so they may enter and benefit from being there.
Jesus says,
"'Come to Me, all you who labor and are heavy laden, and I will give you rest. Take My yoke upon you and learn from Me, for I am gentle and lowly in heart, and you will find rest for your souls. For My yoke is easy and My burden is light.'" (Matthew 11:28-30)
Ones would love to just jump and fly over the wall, and feel peace and have God solve all their problems. But Jesus says we need to take His
"yoke" upon us. This has us in personal connection and union with Jesus and one another. But we need to learn how to submit to Jesus in this yoke.
Therefore, salvation starts with major correction > Hebrews 12:4-14. We need to actively seek our Father for this correction which makes our character submissive so we can obey Jesus in His love and leading. And we discover how our Creator makes us creative for how to love each and every person. This includes prayer, so we are trusting people to God and not playing God, ourselves!
Therefore, we see how this fits with how Jesus says we need to deny ourselves, in Luke 9:23. Our old self's free will has to die so we can freely flow with Jesus in His yoke.
Praying about and thinking about what He has us doing at every moment would take too much time. We need to submit and flow with Him . . . in how He personally rules us in God's own peace >
"And let the peace of God rule in your hearts, to which also you were called in one body; and be thankful." (Colossians 3:15)
Can you imagine an ox being in a yoke, and every minute or two the ox says, "Wait, I need to stop and pray and think about if I want to keep pulling the plow on the line where you are guiding me"?
Jesus is
"gentle and lowly in heart" in us, in our emotions, feelings, thinking, and how we are reacting,
"and you will find rest for your souls." (in Matthew 11:28-30) Jesus is not the one who wastes people and tears people apart with dominating and dictatorial drives for pleasure, while they are being eaten alive by unforgiveness and raging anger and bitterness and desperation for pleasure to try to make themselves feel something nicer. But Jesus is kind to us while we are submitting > submissive to Him, in His yoke.
This is guaranteed if we come to Jesus and deny ourselves and turn from our life of sin. We turn to Jesus, which means we take His yoke upon us and submit to Him. And He changes us so it is our nature to not sin, while we become busy with seeking real correction and submission to Him.
We can not keep our self with its ability to sin to hell, and be in the yoke of Jesus, at the same time. We have been turned
"from the power of Satan to God" > Acts 26:18. And God is now working in our wills >
"for it is God who works in you both to will and to do for His good pleasure." (Philippians 2:13)
But are we perfectly not sinning? My opinion is no, but we are growing. Even children of God who are mature can still be wrong somehow; this is why we are told to relate with one another
"with longsuffering" > Ephesians 4:2 > and
"forgiving one another, even as God in Christ forgave you." (in Ephesians 4:31-32) So, yes we can sin, but also we can forgive "even as God" ! ! !
"But evil men and impostors will grow worse and worse, deceiving and being deceived." (2 Timothy 3:13)
So, our main attention, then, is not to if we sin or not or worrying about how we could lose our "saved" label. Stay attentive to how God is personally correcting and ruling us so we grow in how Jesus has loved us while being so sweetly delighting to our Father >
"And walk in love, as Christ also has loved us and given Himself for us, an offering and a sacrifice to God for a sweet-smelling aroma." (Ephesians 5:2)
Fear of hell and fear of losing our salvation is not the motive which can have us doing this. Our attention needs to be to following the example of Jesus, and winning people by our example > like how Christians wives can help any disobedient husband > 1 Peter 3:1-4 <
"without a word", by their example
. . . in the sight of God > 1 Peter 3:4.