A mikvah generally serves to restore a person to a state of ritual purity. For the most part, this is not relevant in post-Temple times when (a) we cannot become entirely pure and (b) there is little reason to become pure (read more about that here).

Now, married women immerse in the mikvah as part of the laws of Family Purity, which are as relevant today as ever. The mikvah also serves as part of the process of converting to Judaism for both men and women.

But how about men immersing regularly in a mikvah? There are two primary reasons why, even nowadays, many men immerse.

Ezra’s Enactment

At the beginning of the Second Temple period, Ezra the Scribe decreed that a man who becomes impure due to seminal emission should not learn Torah before immersing in a mikvah. This is referred to as takanat Ezra, “the enactment of Ezra.” Subsequent sages added that neither should he pray before immersing. This immersion is called tevilat Ezra, “the immersion of Ezra.”

This enactment was never accepted by majority of the Jewish people. At a later time, it was annulled because it led to the cessation of Torah study (by those who had become impure and did not have a chance to immerse) and/or the neglect of the mitzvah to procreate (by people who chose not to be intimate with their wives rather than have to immerse).1

Most halachic authorities are of the understanding that the entire enactment was rendered null, and this has become the accepted halachah. However, Rabbi Hai Gaon and others are of the opinion that the later decree not to pray before immersion remains in force.2

In deference to this minority view, many have the custom to immerse in a mikvah before praying. Furthermore, all would agree that it is virtuous to follow this practice and that one’s prayer is “more accepted” following mikvah immersion.3

In fact, Maimonides4 attests that it was the custom in North Africa and Spain not to pray after a seminal emission until purifying5 in water, based on the verse, “Prepare to meet your G‑d, Israel.”6 Furthermore, in a fascinating letter, he confides that he personally followed the enactment and never once missed immersing (except when he was very ill); nevertheless, he could not in good conscience state that it is required by the letter of the law.7

The following reasons explain why many immerse on a daily basis, regardless of seminal emissions.

Like a Priest

When we wake up ready to serve G‑d, we are compared to a kohen (priest) preparing to serve in the Holy Temple. Just as a priest would immerse before serving in the Temple (even if he was already pure),8 it is proper to immerse before beginning to pray and serve G‑d.9

Submerging the Ego

The first Chabad Rebbe, Rabbi Schneur Zalman of Liadi, writes that if one's mind has become coarse and dull to the point that he can no longer inspire himself during prayer, there are three things that he should do before praying: (a) give charity; (b) immerse in the mikvah; and (c) learn Torah ethics and Chassidism.10

What effect does the mikvah have on one’s ability to pray? Expounding on the verse “But a spring or a cistern, a gathering of water remains pure,”11 the Chassidic masters explain that when one immerses and is submerged in the mikvah, he is in effect submerged in a much higher state of purity. Once he leaves, however, he is no longer in that same state. This humbling process brings about the nullification of one’s ego.

The Hebrew word for “immersion” (טיבול) is an anagram for the word “humility” (ביטול); immersing nullifies one’s ego and brings humility.12

Playing on the Yiddish saying Men darf tunken zich in mikvah, “You need to dip yourself in the mikvah,” Rabbi Shalom Dov Ber of Lubavitch would say that one must immerse (and lose) his self (ego) in the mikvah.13

Extra Holiness

Even if one is already pure, immersion brings an additional measure of sanctity. This is exemplified by the High Priest, who would immerse five times during the course of his Yom Kippur service—although he had already immersed before he started his service since it was a capital offense to do even the regular service in a state of impurity.14

This is one of the reasons why someone who does not immerse on a daily basis may be particular to do so on a day when the Torah is read, or prior to Shabbat or holidays (immersing before Yom Kippur has other reasons as well).

Strengthening Faith and Understand the Mystical

Additionally, the mystics explain that immersing in a mikvah strengthens a person’s faith and ability to understand the inner, mystical parts of the Torah.15 In fact, tradition states that the Baal Shem Tov merited such lofty revelations due to his regular mikvah immersing.16