If a man takes a vow to Hashem or swears an oath to establish a prohibition upon himself, he shall not desecrate his word; according to whatever comes from his mouth shall he do (Bemidbar 30:3).

In other places, the Torah discusses not lying and keeping a distance from falsehood. However, here the Torah commands us to do according to all that comes forth from our mouths. The difference is clear. When the Torah refers to actual lying, our brains begin working overtime to rationalize "white lies" and promises of other sorts. But when the Torah commands us to do all that we say, it is commanding us to consider every statement a vow unless specifically defined as not being one.

We usually do not take our statements that seriously and do not consider them binding. But the "Man of Truth," Reb Ya'akov Kaminetsky zt"l, was extremely careful never to violate his words, no matter what.

Reb Ya'akov was a Litvack (a person of Lithuanian descent). Consequently, it was odd to find him practicing two Chassidic customs: 1) he would not eat gebrucks (food made of flour dipped into liquids) on Passover and he wore a second pair of tefillin, according to the school of Rabbeinu Tam. Both were because of what he said: once intentionally and the second time perhaps not deliberately.

When Reb Ya'akov was young, he visited a relative in Russia during Pesach. He did not want to rely on their level of kashrus but did not want to slight them either. So he decided to get out of it by telling them that he had accepted upon himself the custom of not eating gebrucks. However, since it was not true, he couldn't say it. To solve the problem, he first actually committed himself to the custom and then he made his declaration. From then on, he never ate gebrucks during the holiday.

When he was the head of Yeshivah Torah VaDaas, Reb Ya'akov was asked by Rabbi Mendelowitz zt"l why he didn't wear Tefillin according to the Rabbeinu Tam, since the Chofetz Chaim ztvk"l did in spite of the fact that he was a Litvack too.

Reb Ya'akov responded that the Chofetz Chaim was 90 years old when he accepted that custom upon himself. He then added casually, "When I'll be 90, I'll wear them too."

I don't know how serious he was at the time, and I don't know if he really expected to live as long as he did, but I remember that as he approached his 90th birthday, Reb Ya'akov began making preparations to purchase a pair of Rabbeinu Tam's tefillin which he then put on every day of the rest of his life.

I once brought my little son Yussie, on his third birthday, to Reb Ya'akov's house to receive his blessing. I mentioned that at twelve o'clock I would be taking him to New York to receive blessings from other great Rabbis too. In the meantime, we talked a while. Suddenly, Reb Ya'akov jumped as if a snake had bitten him. "Oh my," he said, a bit startled. "It's already 3 minutes after twelve and you said you would be going at twelve."

I quickly took my son and left; having witnessed greatness in a great man.

Mas'ei