An excerpt from Rabbi Kaplan's Handbook of Jewish Thought.

Just as we revere God Himself, so must we show the greatest respect for His name, as the Torah states, "[You must] fear this glorious, awesome Name of God your Lord" (Deut. 28:58).

The commandment to respect God's name refers specifically to the ten Hebrew names by which God is designated in the Bible. These names should never be pronounced except in prayer or in study. In all other cases, the colloquial pronunciation is used.

It is permissible to pronounce a word that is identical to a divine name, as long as its connotation implies a secular meaning. For example, it is permissible to pronounce the word Elohim when it is an obvious reference to human judges or false gods, or Tzeva'ot when it refers to armies.

Halleluyah is a composite word meaning "praise God," and should not be used except in prayer since the last syllable is a divine name. At other times, it is customary to pronounce it Hallelukah.

When a divine name is part of another proper name, it is no longer sacred, since it is not translated separately. For example, one may always pronounce such names as Jeremiah, Hezekiah, Zechariah, etc., though the final syllable is the divine name Yah. This is true even when the divine name appears as a separate word, such as in Beit El, since it is still translated as part of the proper name.

It is permitted to pronounce divine names when reading biblical verses, even if only part of the verse is quoted. Therefore, when one comes across a biblical quotation in his studies, it may be read as written, even if it contains God's proper name. In other cases, however, especially when reading a blessing, the colloquial pronunciation should be used.

Similarly, when one is teaching young children to read or say their blessings, it is permissible to pronounce God's name wherever necessary.

It is disrespectful to use God's name as part of any expletive.

Just as we must have reverence for God's Hebrew names, so, too, must we have the greatest respect for His name in any language. It is therefore customary not to pronounce God's name in any language, except in prayer to study, or when proclaiming His deeds. It is disrespectful to use God's name as part of a curse, an oath, or any other expletive such as in the common expressions "G-d damn" or "for G-d's sake."

One who takes God's name in vain or otherwise uses it disrespectfully deserves to be placed under ban. Regarding those who have reverence for God's name, the scripture states, "But for you who fear My Name, a sun of righteousness shall shine with healing in its wings" (Malachi 3:20).

FOUR-LETTER NAME

The Tetragrammaton is called God's "proper name" (Shem HaMeforash). Although God Himself is absolutely unknowable and unnameable, the Tetragrammaton is His highest emanation in creation. It is therefore considered most sacred, and is never pronounced as it is written, even in prayer. We are taught that one who pronounces the Tetragrammaton disrespectfully is worthy of death and has no portion in the World to Come. According to tradition, whenever the Tetragrammaton is written yud-hay-vov-hay, it is read Adonai. However, when it occurs in conjunction with the name adonai, it is read Elohim.

The only place where the Tetragrammaton was ever pronounced as it is written was in the Temple in Jerusalem, as the Torah states a number of times, "God your Lord will appoint a place to link His Name there" (Deut. 12:5, 12:11, 12:21). It was pronounced daily in the priestly blessing in the Temple, as well as ten times during the Yom Kippur service in the public confessions.

In the daily priestly blessing, the Tetragrammaton was vocalized with the vowel points associated with the name Adonai. In the Yom Kippur service, on the other hand, the High Priest would pronounce the Tetragrammaton with its own unique vowel points.

Whenever the Tetragrammaton was pronounced in the Holy Temple, all present would respond, "Blessed be the Name of His glorious Kingdom for ever and ever," as we find, "[Israel] shall bless Your glorious Name, though You Yourself are exalted above all blessing and praise" (Nehemiah 9:5).

On Yom Kippur, those standing closest to the High Priest would prostrate themselves in awe and reverence as the transcendent name of God was pronounced. In commemoration of this, we also prostrate ourselves when the High Priest's confessions are recalled during the Musaf Service of Yom Kippur. According to tradition, one of the ten miracles that occurred regularly in the First Temple was that all present had enough space to bow, even though they stood tightly packed together during the service.

The Tetragrammaton's precise pronunciation was taught only once in seven years.

Originally, the Tetragrammaton was used by all the priests in their blessing. However, there is a tradition that after Shimon HaTzaddik died in 3470 (291 BCE), its use was discontinued, since the Divine Presence (Shechina) was no longer manifest in the Temple and the other priests felt themselves unworthy. However, as long as the Temple stood, it was used by the High Priest in the Yom Kippur service. Still, it was pronounced in such a low voice that it was drowned out by the singing of the other priests in order that it not be learned by the unworthy.

As a sign of reverence, the Tetragrammaton was mentioned as infrequently as possible. Therefore, during this period, its precise pronunciation and significance was taught only to the worthiest students just once every seven years.

Some authorities maintain that it is forbidden to pronounce the spelling of the Tetragrammaton just as it is forbidden to pronounce the name itself. When spelling the name out therefore, we change the letter Heh to Keh, and read Yud-Keh-Vav-Keh.

AWE AND PRAISE

There is also a name of God consisting of 12 letters, as well as combinations of 42 letters, and 72 letters or triads, which are considered Divine names. There is a tradition that these names have miraculous powers if used properly. However, our sages were extremely careful to avoid using them altogether, since one who uses them improperly is worthy of death and forfeits his portion in the World to Come.

One must be extremely circumspect with respect to all mystical matters. Therefore, one may never pronounce the names of any angels not mentioned in the Bible. Since they have a hidden mystical significance, they may only be contemplated silently. Some maintain that they should not be pronounced even when they are found in certain prayers. Those found in the Bible, on the other hand, such as Michael, Gabriel, Raphael, Uriel, etc., and used as personal names, may be pronounced at any time. Even these names were not revealed until after the Babylonian exile, when there was no longer any danger of them being used for idolatrous purposes.

Although it is permissible to pronounce the name Adonai in prayer, it must be done with the utmost awe and respect. One who reads the services as if they were meaningless words is guilty of showing gross disrespect to God.

Similarly, we are warned to adhere to the traditional prayers and not overdo our praises of God, since there are no words which can describe His greatness. Accordingly, the Psalmist exclaims, "Who can express God's mighty acts, or tell all His praise?" (Psalms 106:2).

BLESSINGS AND PRAYERS

It was therefore decreed that one should not say any unnecessary blessing, since it is considered taking God's name in vain. For this reason, in any case where there is a question or doubt about whether a particular blessing is required, the rule is that it should not be said. The only exception is the Grace After Meals (Bircat HaMazon), which because it is a biblical commandment, must be said even where there is a question of its being required.

If one accidentally says an unnecessary blessing, or otherwise pronounces God's name in vain, he should show his reverence and make it into a praise by adding, "Blessed be the Name of His glorious Kingdom for ever and ever."

It is logically inconsistent to bless God for a sin, as it is written, "The robber blesses, but [in so doing] mocks God" (Psalms10:3). Therefore, one should not say a blessing over any forbidden or stolen food, since this is not a blessing but a blasphemy. However, in a situation where non-kosher food is permitted because of mortal danger, one should recite a blessing, since he fulfills God's will by eating it. Similarly, one who must eat on Yom Kippur should recite the proper blessing over his food if he is able.

It is forbidden to pray or even contemplate religious matters in an unclean place.

Covering one's head has customarily been a sign of respect and reverence before God. For this reason, it is forbidden to pray or to pronounce God's name in any manner with one's head uncovered. Since the custom only applies to a man, a woman need not cover her head to pray. Even when a woman does cover her hair, is if forbidden for her to wear a kippah, since she may not wear any garments usually worn by a male.

It is forbidden to pray in a lavatory or bathroom, or any place where people are not properly dressed, as the Torah states, "You must designate a place outside the camp to use as a lavatory… for God your Lord makes His presence known in your camp… Your camp must therefore be holy. Let no nakedness be seen in your midst, lest He turn away from you" (Deut. 23:13-15). It is likewise forbidden to discuss or even contemplate religious matters in an unclean place. Similarly, if one hears a blessing while in an unclean place, he may not respond by saying "amen."

There is a tradition that the word Shalom, meaning "peace," is also one of God's names, as we find, "And he called [the altar] Adonai-Shalom" (Judges 6:24). It was ordained that we use Shalom as a greeting, in order to constantly recall God's name, and because it is an expression of peace. Still, since the word Shalom refers to God, it is never used in an unclean place.

Since the Bible is God's Word, it must be respected as such. Therefore, biblical verses should only be recited in reverence, and not used for jokes, games, or common songs. This does not apply to songs sung at religious gatherings, since they are sung to honor God. Similarly, sacred prayers, such as the Kaddish should not be used as common songs.

UNDER OATH

It is a very serious sin to swear falsely, as the Torah states, "Do not swear falsely by My Name; [if you do so,] you will be desecrating God's Name" (Leviticus 19:12). Similarly, one who swears in vain violates one of the Ten Commandments, "Do not take the Name of God your Lord in vain" (Exodus 20:7). We are taught that the earth trembled when God pronounced this commandment.

There are four types of vain oaths which are forbidden by this commandment. The first two involve a present situation and refer to swearing about that which is either manifestly false or trivially true. The other two involve the future and refer to an oath to do the impossible or to violate a biblical commandment.

Because of their extreme seriousness, one should avoid all oaths entirely. One should therefore not use such common expressions as, "I swear to G-d." Similarly, one should not swear on the life of his children, or on his portion in the World to Come. Whenever possible, one should even avoid speaking to a person who habitually swears.

UTTERING A CURSE

It is an extremely serious sin to curse God in any manner, as the Torah states, "Anyone who curses God shall bear his sin" (Leviticus 24:15). If one curses God using the Tetragrammaton, he is worthy of death, as it is written, "But if one blasphemes the Name YHVH, he shall be put to death" (ibid.).

One who hears a fellow Jew cursing God in any manner must rend his clothing as in mourning…

It is forbidden to curse one's fellow, especially if one uses God's name in any language, as the Torah states, "Do not curse the deaf" (Leviticus 19:14) -- even a deaf person who cannot hear the curse and is not bothered by it. One should avoid cursing another even indirectly, for example by saying, "May you not be blessed." Therefore, one should be extremely careful not to use such expressions as "G-d damn you" or "G-d should only punish you," even if they are not meant seriously.

Just as one may not curse another, so it is forbidden to curse oneself, as the Torah states, "Take heed and guard your life very carefully" (Deut. 4:9). One should therefore be careful not to use such common expressions as "I'll be damned."

One must be even more careful not to curse one's parents. One who curses his parents using any one of God's names is worthy of death, as we find, "Any person who curses his father or mother shall be put to death. Since he has cursed his father or mother, he shall be stoned to death" (Leviticus 20:9).

RESPECT FOR OTHERS

There are other ways in which we are forbidden to injure another with words. Thus, we are commanded not to slander, gossip, or talebear, as the Torah states, "Do not go around as a gossiper among your people" (Leviticus 19:16). Concerning a slanderer, the Psalmist entreated, "May God cut off all slandering lips, every tongue that speaks distortions" (Psalms 12:4), thereby warning us that this is among the most serious of sins.

It is likewise forbidden to cause pain, anguish or suffering, or tease another, or embarrass him in any way, as the Torah states, "Do not vex your fellow man, but rather fear your God" (Leviticus 25:17).

It is forbidden to cause dissent and argument, as the Torah states, "Do not be like Korach and his party" (Numbers 17:5) -- who wrought dissent in Israel.

One should avoid lying and deception, as the Torah states, "Keep far away from anything false" (Exodus 23:7). Similarly, we are enjoined by the prophet, "Let each person speak the truth with his fellow" (Zechariah 8:16). We are likewise taught that God's seal and emblem is Truth (Emet). It is thus written, "The Lord God is Truth" (Jeremiah 10:10). Although it is permissible to hide or slightly alter the truth for the sake of fostering peace and harmony, this should still be avoided as there is a danger that a person might make a habit of lying.

Since all forms of idolatry are an abomination to God, one should avoid pronouncing the name of any idolatrous deity, as the Torah states, "Make no mention of the name of other gods" (Exodus 23:13). However, this only refers to gods whose names are reverenced by their followers, and not those whose names are used in common speech or in personal names. Similarly, it is permitted to pronounce the name of any deity mentioned in the Bible.

It is forbidden to use any foul or improper language, as the Torah is interpreted to say, "Let Him not find a vulgar word [spoken] among you" (Deut. 23:15).

The power of speech is a gift from God. Only man is distinguished with the ability to speak; this ability should not be taken lightly or used for anything degrading. With this in mind, a God-fearing person will carefully guard his speech, as the Psalmist taught us, "Who is the person who truly desires life, who loves the days [of this world] in order to see [eternal] good: Guard your tongue from evil and your lips from speaking deceit" (Psalms 34:13-14).

From "The Handbook of Jewish Thought" (Vol. 2, Maznaim Publishing). Reprinted with permission.