Otherwise Christ would have had to suffer many times since the creation of the world.<quoted text>
Well, the Bible spells it out quite clearly: repent and sacrifice a goat. If you can't afford a goat, then use a dove. If you can't afford a dove, then some fine flour will do nicely. And if you can't afford THAT, then all that matters is sincerely repenting. Paraphrased directly from Leviticus.
Note: NO Jesus required. In fact, worshiping a false god like Jesus will GUARANTEE that your sins are NOT forgiven!
But he (Christ) has appeared once for all at the culmination of the ages to do away with sin by the sacrifice of himself (Christ.)