We are all tempted. Even Christ faced temptation but he never gave in to it.
He released us from the power of sin, we are no longer slaves to it.
Romans 6
17But thanks be to God, that you who were once slaves of sin have become obedient from the heart to the standard of teaching to which you were committed, 18and, having been set free from sin, have become slaves of righteousness.
We sometimes deliberately choose to sin, other times we have sinned in ignorance. But thanks to Christ, no one, Including our own old self, can force us to sin. There is ALWAYS a way to escape it if we look hard enough and choose resist and flee.
1 cor 10
13No temptation has overtaken you that is not common to man. God is faithful, and he will not let you be tempted beyond your ability, but with the temptation he will also provide the way of escape, that you may be able to endure it.
14Therefore, my beloved, flee from idolatry.
We do sin still as believers but we do not make it our habitual practise. If we make it our lifestyle by habitually practicing it then it is evidence we are not born again and the Lord is not working His will and His ways in us by the power of His Spirit. We should always strive to practise righteousness as believers but at times we will and do fall short. We always have the option to turn to God in our times of weakness, and He can deliver us from every temptation if we were completely serious about it. But truth be told we are not able to perfectly exist without sinning in this fallen flesh. It will at times get the better of us sadly, and we are totally responsible for those occasions.
1 john 1
5. This is the message which we have heard from Him and declare to you, that God is light and in Him is no darkness at all.
6 If we say that we have fellowship with Him, and walk in darkness, we lie and do not practice the truth.
7 But if we walk in the light as He is in the light, we have fellowship with one another, and the blood of Jesus Christ His Son cleanses us from all sin.
Sin, Its Reality and Remedy
8 If we say that we have no sin, we deceive ourselves, and the truth is not in us.
9 If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.
10 If we say that we have not sinned, we make Him a liar, and His word is not in us.