The Warning shows each person the sins still on their conscience, i.e. the sins from which they have not yet repented. Those who have many unrepented grave sins will suffer greatly on that day. The best way to diminish that suffering is to repent of your sins well before the Warning (Good Friday, 2016) and then go to Confession.
Every Catholic should make a good confession at least once a month. But as a preparation for the Warning, I strongly recommend confession every week or every other week. And do not be reluctant to examine your life thoroughly and confess every type of sin.
I suspect that a significant proportion of confessions, in the present time, are invalid due to a lack of contrition or a lack of willingness to confess every actual mortal sin, in kind and number. If you are not honest with God in the confessional, then you might not have a valid confession. You must have at least imperfect contrition. You must confess every actual mortal sin that can be remembered after a diligent examination of conscience. And those mortal sins must be confessed in kind and number — the type of sin and the number of times it was committed (approximately and as best you can remember).
Go to Confession frequently!! Or you will sorely regret it on the day of the Warning!
The Warning of Garabandal is the same as the first secret of Medjugorje. These three events, the Warning, Consolation, and Miracle, occur in advance of the start of the tribulation, as a way to strengthen and enlighten all persons of good will so that they might endure the subsequent sufferings with grace.
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