Dreams are a common part of daily life to which the Talmudic Sages attribute great importance. However, on a more careful look, we find conflicting thoughts about dreams in the Talmud and a steadily decreasing concern for them over the ages. As the centuries passed, life changed dramatically and dreams seemed to lose some of their importance. Does that affect halacha?

I. Responding to Dreams

The Gemara (Shabbat 11a) says that fasting is effective to neutralize a bad dream like a fire burns kindling. If you have a bad dream, you may fast even on Shabbat, a day on which fasting is normally forbidden. Another option is mentioned in a different Gemara (Brachot 55b). If you have a bad dream that bothers you, you should gather three friends and have them interpret it positively, i.e., tell you that it is really a good dream. This will eliminate the negative impact of the dream. A further practice is to recite a standard formula (Ribbono Shel Olam) during the priestly blessings (Birkat Kohanim) asking for positive outcomes from your dreams.

This all implies a serious concern for dreams. Similarly, the Gemara (Nedarim 8a) says that if you are excommunicated in a dream, you should gather 10 men to undo the excommunication. The commentators (Ran and Rosh, ad loc.) say that even though this occurred only in a dream, we are concerned that you were excommunicated in Heaven.

And yet, another passage indicates a different attitude. The Gemara (Sanhedrin 30a) says that if your father comes to you in a dream and says that certain money he left for you is forbidden for specific reasons, you can ignore the dream because “matters in a dream have neither positive nor negative impact (divrei chalomot lo ma’alin ve-lo yordin).” We do not rely on dreams for practical matters; therefore you can safely ignore them. (See also Gittin 52a.)

II. Are Dreams Important?

Rav Shimon Ben Tzemach Duran (Rashbatz, 15th cen., Algeria; Responsa Tashbetz 2:128) quotes Rava (Brachot 55b) who contrasts two verses. On the one hand, God says, “I speak with him in a dream” (Num. 12:6), implying that there is divine truth in a dream. On the other hand, “the dreams speak falsely” (Zech. 10:12). Rava answers that dreams transmitted by angels are true but those transmitted by demons are not. According to Rashbatz, the angel here means divine providence and the demon means an unhealthy imagination for any of a number of reasons.

In other words, some dreams are true—messages from Heaven—and some are false, caused by psychological forces, physiological phenomena or otherwise. Therefore, we are left in doubt whether any specific dream is true. We do not divest someone of money for a doubtful claim; therefore dreams have no impact on monetary matters. However, when something is forbidden and easily remedied, we put in the effort to make it permissible when there is even a doubt. Therefore, you should undo an excommunication that occurs in a dream or fast to neutralize a dream.

In medieval times, we start to find authorities questioning whether people still have bad dreams that emerge from a divine source. The Tur (15th cen., Germany/Spain; Orach Chaim 668) quotes R. Amram, R. Kalonymus and R. Eliezer Ben Yoel (Ra’aviah) who say that today (in their day), we do not know which dreams are truly bad and therefore you should not fast on Shabbat over a dream. Rav Yosef Karo (16th cen., Israel; Beit Yosef, ad loc.) quotes other medieval authorities with similar hesitations, but Rav Karo (Shulchan Aruch, ad loc., 5; 288:4-5) does not follow those authorities completely and allows fasting on Shabbat for dreams listed in the Talmud. We find additional concerns in later generations.

III. Should We Worry About Dreams?

Rav Avraham Gombiner (17th cen., Poland; Magen Avraham 288:7) quotes approvingly Rav Yeshayahu Horowitz (17th cen., Germany; Shenei Luchot Ha-Berit, Shabbat, s.v. ve-sa’anis chalom) who says that you should not fast on Shabbat for any dream. Rav Ovadiah Yosef (21st cen., Israel; Yechaveh Da’at 4:24) quotes Rav Horowitz as going even further (I could not find this passage). Adapting a Gemara (Pesachim 110b), Rav Horowitz says that if bad dreams worry you, then you need to be concerned and possibly fast over them. If you aren’t worried about a bad dream, then you have no reason for concern.

But can you control whether you are scared by a bad dream? We can assume that bad dreams are not from a divine source. Therefore, Rav Ovadiah Yosef (ibid.) concludes by quoting Rav Chaim Palaggi (19th cen., Turkey; Ruach Chaim 288:1) that if you have a bad dream on Shabbat, rather than fasting you should say extra Tehillim and study Torah diligently. Elsewhere (Beit Ha-Yayin, Yamim Nora’im, pp. 195-196), Rav Yosef says that if you are worried about a dream, you should just say the verse “the dreams speak falsely” or, if you are very worried, take the standard formula (Ribbono Shel Olam) from Birkat Kohanim and say it on your own on any day. And, if you are very worried and you are greatly pained, then you may follow the Gemara and fast on Shabbat (fulfilling all the halachic details).

Going even further, Rav Avraham Yeshayahu Karelitz (Chazon Ish, 20th cen., Israel; Kovetz Iggerot Chazon Ish, vol. 2, no. 149) writes briefly that personally he just ignores his bad dreams. He continues that if you have a bad dream, say the Ribbono Shel Olam and move on with your day. We cannot just tell someone not to worry about their dream but we can redirect them to a brief verse or prayer.

Rav Simcha Rabinowitz (cont., Israel; Piskei Teshuvot 220:1) explains Chazon Ish’s approach. In modern times people are busier and their lives are more filled with global concerns than in ancient times. Nowadays, dreams are about what we hear during our busy days and the concerns we face in our lives. Therefore, we should not pay much attention to our dreams because they are not divine predictions about the future. Rather, they are manifestations of our thoughts, which might give insight into our psychological well-being but will not tell us what will happen in the future.

The Chazon Ish died in 1953. At that time there were daily newspapers and radio programs so that modern media was spreading news quickly. I am old enough to remember when, if you wanted to get the latest news, you had to watch the news at certain times or listen to the radio every 22 minutes. And if you wanted to check stock prices, you had to read the morning newspaper. Then came 24-hour news channels and financial news. Then came the internet, with breaking news and real-time financial information. Now we have social media, with constant updates and opinions. The pace of life today is much faster than it was 40 years ago, and even more so than it was 400 years ago. Modern communication brings us so much news and information that overwhelm our dreams. If you are worried that your dreams might come true, you can recite the specific verses or formulas about dreams. However, according to Chazon Ish and others, there is no need to do so.

Rabbi Gil Student is editor of TorahMusings.com.