Mirom HaRim: Proverbs 23
The 21st of Shevat is the Yahrtzeit of Rav Yechiel Meir Lifschitz (Lipschutz) of Gustinin [Gostynin; Gastinin] (1816-1888). He was a disciple of Rav Menachem Mendel of Kotsk and of Rav Yaakov Aryeh of Radzymin, after whose death he became chassidic leader in Gustinin. His teachings appear in Merom HaRim and Mei HaYam.
“Purchase truth and do not sell it.” (Proverbs 23) If no one will sell truth, how can we possibly but it?
The explanation is that when a person fulfills a Mitzvah he is acquiring truth. However, if his mind is distracted by physical concerns when performing the Mitzvah, it is as if he has sold the truth he acquired for an insignificant price.