"The fear of the Lord is the beginning of wisdom: and the knowledge of the holy is understanding." - Proverbs 9:10
"And I say unto you my friends, Be not afraid of them that kill the body, and after that have no more that they can do.
But I will forewarn you whom ye shall fear: Fear him, which after he hath killed hath power to cast into hell; yea, I say unto you, Fear him." - Luke 12:4-5
But here is what the Scripture goes on to say:
"Are not five sparrows sold for two farthings, and not one of them is forgotten before God?
But even the very hairs of your head are all numbered. Fear not therefore: ye are of more value than many sparrows." - Luke 12:6-7
The truth is, that once we have believed on the Son, Jesus Christ, we have nothing left to fear. We can know that we are saved, born again, passed from death to life, sealed by the Holy Spirit. God's wrath no longer remains upon us because of Christ's sacrifice, which we receive, as a gift, by grace, through faith. Christ has not failed in what He came to do, "It is finished!" (John 19:28-30)
It is not about our "obedience" or good works, it is about Christ's finished work on the cross. We rest in Him. (Hebrews 4)
Also, remember Jesus' words, recorded in Scripture:
"And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up:
That whosoever believeth in him should not perish, but have eternal life.
For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
For God sent not his Son into the world to condemn the world; but that the world through him might be saved.
He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God." - John 3:14-18
And also:
"Labour not for the meat which perisheth, but for that meat which endureth unto everlasting life, which the Son of man shall give unto you: for him hath God the Father sealed."
"Then said they unto him, 'What shall we do, that we might work the works of God?'"
"Jesus answered and said unto them, 'This is the work of God, that ye believe on him whom he hath sent.'" - John 6:27-29
"For I came down from heaven, not to do mine own will, but the will of him that sent me.
And this is the Father's will which hath sent me, that of all which he hath given me I should lose nothing, but should raise it up again at the last day.
And this is the will of him that sent me, that every one which seeth the Son, and believeth on him, may have everlasting life: and I will raise him up at the last day." - John 6:38-40
Read also: Romans 3, Romans 5, Galatians 5, Hebrews 10, Hebrews 11
We do not need to be afraid that Jesus will reject us because we are not good enough. He is faithful to His promises, and He has promised never to leave us or forsake us.
God bless you.