Christ died for all our sins past present and future but this does not negate us from asking forgiveness and being cleansed by the blood. In fact the bible states that  for us to walk in the light we MUST confess sins to be cleansed (1 Jn.1:6-9)

There are certain teachers telling people to ignore this, that their future sins have all been forgiven so there is no need to repent or confess. Jesus paid the price for all our sins in the past but for us to claim whatever sins we commit in the future are already forgiven is is a flawed interpretation of  how God asks us to react to when we sin.

What happens when we sin against another person or they against you? We are to reconcile with them. We do not go to them or they to us and and say there is no problem, its already forgiven.

Matt 18:15-16 "Moreover if your brother sins against you, go and tell him his fault between you and him alone. If he hears you, you have gained your brother. "But if he will not hear, take with you one or two more, that 'by the mouth of two or three witnesses every word may be established.” Or for specific sins,  James 5:16 Confess your trespasses to one another.”

If we do this with man how much more important is it to do with God.

1 Jn.1:5-10 This is the message from the beginning is God light and darkness indicates sin that affects fellowship with Him, “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. If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. If we say that we have not sinned, we make Him a liar, and His word is not in us.”

God says, No confession- no cleansing. Why, because we are not walking in the light. We are to be walking in the truth and to do this one must know what  is right and what is wrong and when we step over the line. Confession means agreeing with God that something was sin. Of course one cannot confess everything they think or do wrong but they can what they do know, and God expects this from mature spiritually minded saints. If we confess what we know, He is faithful .. and will cleanse us from all unrighteousness. he cleanses all of them, even the ones we don’t know. Its about having an attitude of wanting to be cleansed and right with others. It has been said, the quicker one confesses the more mature they are.

Confessing is saying the same thing. If we confess homologoomen Third-class condition - present active subjunctive of homologeoo ("if we keep on confessing)."

1 John 1:7 cleanseth us from all sin. Means to continue to cleanse us, Cleanseth katharizei in the present tense. The cleansing is present and continuous. (from Vincent's Word Studies of the New Testament).

1 Jn. 1:7 heemas, continues to cleanse us, i.e., to keep clean what it has made clean” (from Adam Clarke's Commentary) see 1 Thess 5:23.

v.8 “If we say that we have no sin, we deceive ourselves, and the truth is not in us.”

 Here John speaks of the presence of sin, that sin is present..

v.9 “If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.”

“If” is a condition. Sins is plural, as compared with the singular. The plural indicates that the confession is to be specific as well as general.

1 John 1:9 Sins. Note the plural, as compared with the singular, sin, in the previous verse. See note. The plural indicates that the confession is to be specific as well as general (Vincent's Word Studies of the New Testament)

Sinned -“Perfect active indicative of hamartanoo (NT:261). This is a denial of any specific acts of sin, while in 1 John 1:8 we have the denial of the principle of sin. (Robertson's Word Pictures in the New Testament)

We do not have to make daily sacrifices for sin because Christ’s sacrifice is once for all and effacacious But we do need daily confession of what we know we did wrong (intentionally or even not intentionally) for cleansing. Cleansing is not just a one time act at salvation, the atonement is.

We do not want to be one that is spoken of in V.8 “If we say that we have no sin, we deceive ourselves, and the truth is not in us.” He then repeats the idea V.10 “If we say that we have not sinned, we make Him a liar, and His word is not in us.”"have not sinned" is of sins to the present time: not merely sins before, but since salvation.  Notice that John continually uses the word IF. Its a conditional word that questions our actions.

Sins are committed because of the old nature is still with us. This one reason Peter says “For he who lacks these things is shortsighted, even to blindness, and has forgotten that he was cleansed from his old sins.” (2 Peter 1:9). palai- 1) of old, former 2) long ago.

We should be encourage and assured by what John further writes. 1 Jn. 2:1: “My little children, these things I write to you, so that you may not sin. And if anyone sins, we have an Advocate with the Father, Jesus Christ the righteous.”

John clearly taught as Paul did, as Peter did, that we do still sin and we need to be aware of sin to confess them,  that we are cleansed by the blood. Our fellowship will be restored by means of confession. It is a cleansing for a clear conscience and being useful for the Lord. He will not use those who are in continual sin and will not turn from  the practice.

Eph.5:14-17: “See then that you walk circumspectly, not as fools but as wise, redeeming the time, because the days are evil. Therefore do not be unwise, but understand what the will of the Lord is.”

The only way to be wise in this manner is to know what sin is and avoid it, and if it is done, to confess it. The quicker it is done our conscience will be cleansed and this being practiced will bring spiritual growth.