Because that is the whole point. If we don't try, we don't grow in holiness; if we don't try, we aren't truly saved (remember 1 John 1:7-10).If it is impossible, what is the point of trying ?
Yet, none of that says we are now morally perfect and sinless. We have been delivered from the kingdom of darkness to the kingdom of Christ, but we still live in this world, in the flesh with its sinful desires and passions. We are covered by the blood of Christ, which means we are justified and are secure in Christ.Paul wrote..."And you hath he quickened, who were dead in trespasses and sins;
Wherein in time past ye walked according to the course of this world, according to the prince of the power of the air, the spirit that now worketh in the children of disobedience:
Among whom also we all had our conversation in times past in the lusts of our flesh, fulfilling the desires of the flesh and of the mind; and were by nature the children of wrath, even as others." (Eph 2:1-3)
Are you still dead in trespasses and sins ?
Are you still walking according to the course of this world ?
Is the spirit of disobedience still in you ?
Are you still by nature a child of wrath ?
If not, you are sinlessly perfect, made righteous by faith in Christ.
And these verses apply to you..."But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets;
Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe:" (Rom 3:21-22)
What this does is breaks the power of sin in our lives; we can choose to not sin and grow in holiness, through the power of the Holy Spirit. But nowhere is it promised in the Bible that in this life, before we enter heaven, that we are now perfect and sinless or that we can attain that. Sin will be a continual struggle until we die.
2Ti 2:14 Remind them of these things, and charge them before God not to quarrel about words, which does no good, but only ruins the hearers.
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2Ti 2:16 But avoid irreverent babble, for it will lead people into more and more ungodliness,
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2Ti 2:22 So flee youthful passions and pursue righteousness, faith, love, and peace, along with those who call on the Lord from a pure heart. (ESV)
2Ti 3:16 All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness,
2Ti 3:17 that the man of God may be complete, equipped for every good work. (ESV)
1Jn 1:8 If we say we have no sin, we deceive ourselves, and the truth is not in us.
1Jn 1:9 If we [continually] confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.
1Jn 1:10 If we say we have not sinned, we make him a liar, and his word is not in us.
1Jn 2:1 My little children, I am writing these things to you so that you may not sin. But if anyone does sin, we have an advocate with the Father, Jesus Christ the righteous. (ESV)
1Jn 5:16 If anyone sees his brother committing a sin not leading to death, he shall ask, and God will give him life—to those who commit sins that do not lead to death. There is sin that leads to death; I do not say that one should pray for that. (ESV)
Such warnings for believers are abundant throughout the NT, but would be pointless nonsense if believers are already perfectly sinless.
Of course.Got faith ?