Is there a specific date that commemorates Jesus death? if not, why not?
There IS a specific date on which Jesus died, it’s the third day before Passover. On the Jewish Calendar, this happens on the same date every year, the 14th day of the month Nisan.
— UNfortunately — the Jewish Calendar is not the same as our Western one (and sometimes even has a “leap month” put in), so the date of Passover keeps being different dates on our Western system.
You are already familiar with this, because Easter is “our” celebration of the death and resurrection of Jesus, and you know how Easter keeps moving about? It moves according to the Jewish calendar.
People have tried to calculate exactly which date on “our” calendar Jesus died. It’s not too hard, to do, but the Western date will depend on which year He died, and so exactly when Passover came on our calendar that year.
So some people try to work out which year he died, then they can easily work out a “Western Calendar” date.
We know it has to be within the range 26AD to 36AD, because those are the years the Romans recorded that Pontius Pilate was appointed, and removed, from office.
Working out some of the other historical data present in the New Testament accounts, the most popular possible date of Jesus’s death is April 7th in the year 30 AD.
So why don’t we celebrate this date? Well neither Jesus nor any of his contemporaries would have recognised our dating system, so the question has to be, “Why WOULD we celebrate it then? And – “Why NOT celebrate on the date they WOULD have recognised?”
Just enjoy Easter!