The Talmud teaches that our sun returns to its original location in the heavens, on the same date and time it was created once every 28 years. Every 28 years - once in a generation - the sun reaches the vernal equinox (on the Hebrew calendar) on a Wednesday morning, the fourth day of the week, the day, according to the Torah, when God created the great lights. Such an anniversary became, for the rabbis, an opportunity for blessing, study and celebration.

Our next opportunity for this celebration is Wednesday morning, April 8 - also, by the way the day of the first Passover seder. (The computation of this day, and the differences between the Hebrew calendar's and the Gregorian calendar's vernal equinox are quite complicated. For more information about this and other aspects of the calendar, visit blessthesun.org).

The tradition suggests that people should gather in large groups (at least 10, which is the amount required to hold a formal Jewish religious service), but the more the merrier) before dawn on the appointed day and wait to see the first rays of the sun's lights. The short service that is recited includes appropriate psalms for the occasion and one blessing: "Baruch ata adonai, eloheynu melech ha'olam oseh ma'aseh bereshit. Blessed are you God, Sovereign of all life, who fashions the work of creation."

This special blessing, called "Birkat HaKhamah (Blessing of the Sun)," provides us with a rare, yet invaluable opportunity to think about, reflect on and celebrate the role the sun plays in making our lives, indeed all life on Earth, possible.

The light, heat and energy provided by the sun makes it possible for us, and all creation, to live on what would otherwise be a cold, lonely and dead chunk of rock. It is not at all surprising that many ancient (and even contemporary) cultures worshiped the sun or placed a deity of the sun among the highest echelons of their pantheons. The Jewish tradition, however, recognizes that the power of the sun, as great and awesome as it is, comes to us not of its own accord, but because God, the source of all life, created it. No matter how literally or metaphorically we take the story of Genesis to be, we know that life is a gift, to be appreciated, treasured, valued and most of all, guarded and preserved. Reciting Birkat HaKhamah once every 28 years gives us the opportunity to say thank you for this wonderful gift of life.

In this era of looming ecological crisis, climate change and dwindling energy resources, it is more important than ever that we do our part to guard and preserve life - all life - on this planet. Birkat HaKhamah also provides us an opportunity to look at ways we can contribute to decreasing our carbon emissions, reducing our dependence on fossil fuels and redesigning our lives for economic and environmental sustainability.

At Congregation Agudas Achim, we have started down this path by replacing as many bulbs as we can with CFL bulbs (which use less electricity and last longer) and by instituting recycling when we can. We recently hosted the film series "The Green Reel," which raised awareness about sustainability.

But we have more to do. We are currently exploring the possibility of installing solar panels on the southern facing side of our roof. We need to be more vigilant with our recycling program and more persistent in encouraging carpooling and ride sharing to synagogue functions. We may even want to think about installing a solar replacement for the congregation's eternal lamp, which lights the ark that contains the holy scriptures. And look for the return of the "Green Reel" series next year.

And, of course, we need to bless the sun. Congregation Agudas Achim members will be gathering at 6 a.m. at Capron Park in Attleboro on the morning of April 8 for a short "Birkat HaKhamah" service. Consider joing us, or at least taking the time that morning to look up and great the sun with a special sense of gratitude.

Rabbi Elyse Wechterman is the spiritual leader of Congregation Agudas Achim, a Reconstructionist synagogue in Attleboro.