Is the Bible Simple to Understand?

I believe in SOLA FIDE, Faith is the act of acceptance of what God has told, therefore you’re saved by faith alone, but saving faith is not alone. Within that framework i do believe in Grace alone, but i do not take the frame work of Grace as a license to sin.
Because anyone who sins is of the devil, i believe in the willful act of repentance from our heart is an essential factor, because it is the evidence of the work of the HolySpirit when it comes to sanctification. I think, these implications can see throughout the gospels.

Once you’re saved you’re always be saved because God knows our Heart before the foundation of the world and he has his elect. I believe his elect will exhibit, the evidence of his standard through the Holyspirit. Which then influence their willful acts. I believe God maintains his justice, when it comes to the influenced willful act.