One of the practical problems that we face is that we keep repeating the same sin. Many of us confess a particular sin and then shortly thereafter commit the same sin again. Does this mean our confession was not genuine? Not necessarily. In cases like this we need to realize that God in His grace has made provision for our repeated failures.
Continuous Confession
In
1 John 1:9 the word translated if is in what as known as a conditional sentence. It can be better translated
If and it is probably that you will have to. . .
Hence the text assumes that we will have to keep on confessing. The verb confess is in the present tense denoting continued, repeated, action. It can be literally translated, Keep on confession as a habit of life. God has provided this remedy because He is aware of our human weaknesses.
Confession looks backward to what we have done. It takes care of past sins already committed. It is primarily curative of something that has happened. It does not, in and of itself, give power for us to overcome temptation next time it hits.
Summary
When we continue to repeat a sin we must continue to confess that sin. Though confession does not give us the power to overcome a particular sin it does remind us that the act we are confessing is sinful.