The passuk states “לא תשא את שם ה’ אלקיך לשוא כי לא ינקה ה’ את אשר ישא את שמו לשוא.” Simply this means “Do not swear in the name of Hashem for naught, since Hashem will not make innocent he who will swear in His name for naught.” This passuk prohibits swearing in vain with the name of Hashem. Once the Torah warns a person, “לא תשא את שם ה’ אלקיך לשוא, do not to swear for naught,” why does the Torah need to repeat “את אשר ישא את שמו לשוא, he who swears for naught?”
Onkelos translates this passuk as “Do not swear for naught, since Hashem will not make innocent he who swears falsely.” The Nefesh HaGer says, Onkelos translates the word לשוא with two different meanings in order to answer this question. The first לשוא means for naught (למגנא); for example, do not swear about a tree that it is a tree or a stone that it is a stone. Everyone knows this and there is absolutely no point in swearing about it. The second לשוא means falsely (לשקרא); do not swear to change the truth, for example, do not swear about a pillar of stone that it is gold, and certainly do not swear about something which is a lie that no one knows about. The Radak explains that the word שוא connotes two explanations שקר, a lie, and חנם, for naught. This is as it states “לשוא הכיתי את בניכם, for naught I smote your children.” The Yerushalmi brings, one who swears about figs that they are figs will receive lashes for swearing for naught, just as Onkelos translates לשוא,” למגנא, for nothing.”
The Nefesh HaGer asks, since Onkelos translates the beginning of the passuk with “do not swear for naught” how does it follow to translate the second part as, “he who swears falsely.” These are two different types of oaths, what is the connection between them?
The Chizkuni answers that the passuk warns a person, do not accustom yourself to swear for naught in the name of Hashem. The reason is because this will cause you to also swear falsely in the name of Hashem, which Hashem will not make innocent. The Nefesh HaGer adds b’shem the Ibn Ezra, the issue of not swearing for naught is people think that one who swears for naught did not transgress a bad aveira. However in truth it is worse than all the lavin which follow it, do not murder, steal a person, or be immoral. One may be afraid to murder, steal a person, or commit immorality at a time that he desires, therefore he will be somewhat limited. However one who accustoms himself to swear for naught will come to swear numerous oaths in vain in one day. He will say “I swear,” as part of his regular talk. He will become so accustomed that he won’t even realize that he swore in vain and did an aveirah. If one will rebuke him for swearing in vain, he will deny by taking another oath that he didn’t swear. A person who constantly swears in vain will end up swearing falsely and profane the name of Hashem.
The Ramban brings b’shem Rabboseinu: the passuk states קרבן לה’ an offering for Hashem which reflects that a person should specifically say “עולה לה’ a burnt-sacrifice for Hashem” or “חטאת לה’ a sin-offering for Hashem,” and not “לה’ עולה , for Hashem a burnt-sacrifice” or “לה’ חטאת , for Hashem a sin-offering,” The Malbim explains the reason is because it is improper to mention Hashem’s name at first on nothing. Therefore the type of offering should be mentioned first and only afterwards should he place Hashem’s name upon it. The Sifrei adds: if when a person sanctifies an animal the Torah warns not to mention Hashem’s name for naught, for sure when one talks one should be careful not say Hashem’s name for naught!
May we train ourselves to be careful from saying Hashem’s name in vain or by way of a lie.