What is the commodity that each one of us possesses every moment of our lives, yet we never have enough of it? It is with us as long as we live, yet it cannot be seen or felt or heard. We do everything we can to save it, yet we never stop spending it, and we always run out of it. We make it and cherish it, yet we also waste it, and sometimes even willingly kill it. At times it crawls, and at other times, it flies.The answer, of course, is time.Judaism is a religion of time. The first thing which God calls holy is neither a person or a place, but Shabbat, an island, or better, an oasis, in time. The first commandment which God gave to the Jewish people as a nation was the command to establish a calendar and take control of our time.The writer is director of the Jewish Outreach Center of Ra’anana.Much of Judaism’s halachic life is governed by time: We have a time by which we must pray each day, a specific time when Shabbat starts and ends, ushering in countless dos and don’ts; the time when we must sever our connection to leaven on Pessah; times during the year when eating is mandated and required, and times when it is prohibited.In ancient times, we plotted time by the sun, and sometimes by the moon, and we were fairly expert in the movements of the celestial bodies by which we calculated our days and months and seasons. In more recent times, we learned to depend on our watches, an apt name, because a Jew is constantly watching the time. In a sense, we all are “watchmen,” ready to guard Jewish tradition.Jewish life, in many ways, is also a time machine. On Shabbat, we leave the harriedness and hurried-ness of the daily grind and climb into our time machine to travel to the world of Shabbat, the same world of candles and halla and cholent that our parents and grandparents and ancestors inhabited. On Rosh Hashana, we recite the same prayers our extended family has been saying for centuries and listen to the sounds of the shofar that have been part of our collective memory for thousands of years.And on Yom Kippur, we are transported to a world of teshuva, repentance, in effect locked in a room for 25 hours with God where we can hopefully repair our relationship with Him. We hear the ancient hymns; we join, as it were, with the high priest in his Avoda service in the Holy of Holies; we even fast all day in order to sacrifice some of our own flesh in solidarity with the Temple offering. Closing my eyes on the holidays, I find myself moving back in time, tasting again my mother’s kreplach, choosing a lulav and etrog with my zayde, singing “Maoz Tzur” with my family around the menora, standing in awe of the people holding the Sifrei Torah at Kol Nidre.I connect across space and time and become a Jew of the ages.God’s greatest gift to us is time. It’s what we pray for when we ask God to write us into His Book of Life, to grant us more time. But at the same time, it’s what we do with our time that really matters. King David expressed this well when he said, “Teach us to number our days wisely, so that we may attain a good heart and a good name.”For the sages, every moment was precious.For them, the worst offense was wasting time that could better be used to study or fulfill a mitzva. In fact, says the Talmud, whenever a person experiences a negative event in his life, he should examine his actions. And if he finds that he did nothing wrong to justify that event, he should assume his problem has come about because of the sin of wasting time.One of the most beautiful Jewish blessings is the Shehecheyanu, in which we thank God for having kept us alive and sustained us and brought us to this time. To be a Jew is to see life as a blessing and make a blessing over life. As in all things Jewish, the Hebrew word defines the essence. Z’man, time, is somehow connected to hazmana, invitation. Not because every invitation contains a time (though why Israeli invitations even list the time is beyond me) but because time itself is an invitation to take this gift and use it well, to its fullest extent.Like the cellphone or the computer, time can be both our servant and our master, depending upon our discipline and approach. “Time is a tyrant,” goes the famous saying, but that is precisely why God commands, in that first mitzva, hahodesh hazeh lahem, make this time yours – you control it.ON YOM Kippur, we all are asked to become surgeons and perform a very delicate, often painful procedure on ourselves: It’s called heshbon nefesh, taking stock of who we are, what we are, where we are. It is not for the faint of heart. And a large part of that process is deciding what we do with the time allotted to us. In short, we are to conduct a thorough self-examination to see what “makes us tick.” Our lives are not an open book; they are, rather, like a Torah scroll. When you read from a Torah, you open the scroll to reveal just the part that is relevant for the here and now. Yes, there is a past and we are destined to repeat it; and there is also a future, and we will come to that as well. But for now, the only part of the Torah which is revealed to us is that which we see right in front of us. Time opens up a window of opportunity.The past, as they say, is history and the future a mystery, but the present is right here and now. It is waiting for us to do something of value, to bring meaning to our lives, to utilize the amazing strengths and talent and potential which God placed in each one of us. Soon, that window will close, that scroll will roll on and that opportunity will be gone.We have to take time into our hands like the handles of the Sefer Torah and turn it into something beautiful and valuable.Rabbi Yisrael Meir Kagan, known popularly as the Hafetz Haim, was one of the last century’s rabbinic giants. He made the famous observation that life is like a picture postcard.He noted how when people are on vacation, they often send their friends and family a postcard. Now, the space on a postcard on which you can write a personal message is limited to one half of one side. When the person starts writing, he usually uses big letters and takes up a lot of space with just a few words. But then, as he gets nearer and nearer to the end of the space, and realizes that he still has a lot to tell, he writes smaller and smaller, trying to cram as many words as he can into the tiny area that’s left to him.So it is with life, says the Hafetz Haim. During most of our life, we feel we have all the time in the world, so why rush, why try to do too much? There will always be more time tomorrow. But then, as we grow older, and perhaps a little wiser, we find that we have so much left to accomplish and so little time in which to do it. So we end up stuffing a lot of life into a very small space, and very often run out of room – and time.The blessing we all hope for is to not only be granted the gift of time, but to know what to do with it, to be able to appreciate it, to budget and utilize it so that the picture postcard of our lives comes out neat and orderly, diverse and developed, yet divinely dignified.We ask God to grant years to our life, and life to our years. When we look back, will we have that secure feeling that we did all we could to justify the life which God gave us? Did we fill up our years with value and values? The answer to those questions awaits us in a better place, where only time will tell.