The mystics of our tradition saw great meaning in the counting of the Omer. In its cycle of 7 days, counted 7 times, they saw a parallel to the sefirot, Divine attributes of Jewish mystical understanding. Each week, then, was dedicated to a particular attribute—this week’s attribute is Netzach—tenacity.

Today is the 25th day of the Omer.

How do we tackle obstacles that seem insurmountable? It’s hard enough for us to change ourselves, how do we change the world?

Persistence is the key: never giving up on the belief that you can make a difference, that you can help shape the future.

When I was six months old, Earth Day was created on April 22, 1970. It was the beginning of the modern environmental movement. A broad group of concerned citizens, scientists, and environmentalists came together to prevent oil spills, cease the indiscriminate use of pesticides, counteract smog caused in part by leaded gas, and slow the proliferation of toxic dumps.

All these years later we can be grateful for progress that has been made. But we know that there is so much more left to do. Climate change poses an existential threat to humanity and our window of opportunity to make a difference is rapidly closing.

For the generations to come—and for ourselves as well—we must be tenacious and persistent in our work as we tackle this global crisis. On this Earth Day, let us find inspiration in the prayer of Rabbi Nachman of Breslov (1772-1810) and reflect on how we can help to make a difference:

“Grant me the ability to be alone; may it be my custom to go outdoors each day among the trees and grass—among all growing things and there may I be alone, and enter into prayer, to talk with the One to whom I belong. May I express there everything in my heart, and may all the foliage of the field—all grasses, trees, and plants—awake at my coming, to send the powers of their life into the words of my prayer so that my prayer and speech are made whole through the life and spirit of all growing things, which are made as one by their transcendent Source. May I then pour out the words of my heart before your Presence like water, O Eternal, and lift up my hands to You in worship, on my behalf, and that of my children!”

— Rabbi Yoshi Zweiback