Repent, believe in your heart, confess with your mouth. It is not a magic formula to never sin again.
Yes it is, believe, that is true faith with works.
James 2:20 But wilt thou know, O vain man, that
faith without works is dead?
Repentance is followed by the keeping of the commandments:
Ezekiel 18:21 But
if the wicked will turn from all his sins that he hath committed, and
keep all my statutes, and do that which is lawful and right,
he shall surely live, he shall not die.
27 Again,
when the wicked man turneth away from his wickedness that he hath committed, and
doeth that which is lawful and right,
he shall save his soul alive.
Ezekiel 33:14 Again, when I say unto
the wicked, Thou shalt surely die;
if he turn from his sin, and do that which is lawful and right;
15 If the wicked restore the pledge, give again that he had robbed,
walk in the statutes of life,
without committing iniquity;
he shall surely live, he shall not die.
19 But
if the wicked turn from his wickedness, and
do that which is lawful and right,
he shall live thereby.
If you continue in sin, you have neither repented nor believed, but are in darkness even until now:
1 John 2:9 He that saith he is in the light, and hateth his brother,
is in darkness even until now.
Once you repent and believe you can't sin, because you have His Seed, and He cannot sin:
1 John 3:6
Whosoever abideth in him sinneth not: whosoever sinneth hath not seen him, neither known him.
9
Whosoever is born of God doth not commit sin; for
his seed remaineth in him: and
he cannot sin,
because he is born of God.