If a man makes a vow to HASHEM or makes an oath to prohibit himself, he shall not profane his word; according to whatever came out of his mouth, he shall do. (Bamidbar 30:3)
In search of the “Roots of the Mitzvah”, The Sefer HaChinuch hearkens back to the 3rd of the Ten Commandments, “You shall not take HASHEM’s name in vain…” He writes, “From the roots of this commandment are for people to know and fix in their souls and strengthen the faith in their hearts about G-d, blessed be He – who is in the Heavens above and exists forever – that there is nothing else like His existence. And it is fitting and obligatory upon us when we mention His great name upon our actions and upon our words, to mention it with fear, with awe, with trembling and perspiration; and not like those that joke and speak about something light, such as the things that exist and perish and do not continue to exist – like us people, and the other things of the lowly world…”
The essential root of the matter is to remember and keep in mind the disproportionate greatness of HASHEM as compared to us and our earthly stature. Perhaps there’s another dimension at play here as well. We are invited by the Torah to emulate the Almighty and walk in His ways. Every day we say in our prayers a paragraph known as “Boruch Sh’Amar”. It reads, “Blessed is the One Who spoke and brought the world into existence. Blessed is G-d! Blessed is the One Who maintains creation. Blessed is the One Whose words are deeds; Whose decrees are fulfillments. Blessed is the One Who has compassion upon the world and all its creatures. Blessed is the One Who rewards those who are reverent. Blessed is the One Who lives forever and endures throughout eternity. Blessed is the One Who redeems and rescues. Blessed is G-d’s name! Blessed is HASHEM our G-d, Ruler of the Universe, G-d the merciful Father. You are praised by the words of Your people, extolled and glorified by the words of Your devout ones and servants and particularly by the words of your servant David. With praises and songs shall we laud You, HASHEM. We shall exalt You, praise You, and glorify Your Name, our G-d and King. O Unique One, Life of the Universe, praised and Glorious King, Your Name is Eternal. Blessed are You, HASHEM, King who is lauded with praises.”
Embedded in that sublime laundry list of holy attributes that HASHEM is praised for is; He spoke and world came into being and He does what he says, and He fulfills His decrees. We are Commanded therefore, “he shall not profane his word; according to whatever came out of his mouth, he shall do.” This is a lifelong focus and trait to acquire. It is mentioned that HASHEM is praised by the words of the great ones, but it is not their words alone which is the source of their and His great praise.
Words are real! HASHEM spoke and the world came into being! The entire world is built from words! HASHEM breathed the breath of life into man and with that Divine breath we became speaking creatures. The integrity of our beings -our spiritual credibility is based on the value we give our own words. Our world is built on words backed by our actions. Words are like checks. Deeds are like money in the bank! I can write a big check but if the there is no money in the bank, the check will bounce up to the sky. A man can say I love you but while some task of import remains undone, the words ring hollow. Words must be backed by action or they are not G-d-ly words. They are no longer profound words. Rather they are downgraded to profane!
It is told about Rabbi Yaakov Kaminetsky ztl. that when he was a Yeshiva student in Europe he was set up to eat on Pesach by a family whose Kashrus was questionable. In order to excuse himself from that invite without offending the family he declared, “I do not eat Gebruchts (Matzah that is combined with water) on Pesach”. In fact, his custom, like most Lithuanian Jews was to eat Gebuchts. From then on, for the rest of his long life he did not eat Gebruchts. This was in order that that single statement that exited his young mouth should not prove untrue, and his word was pure gold.