Commentary for Leviticus 27:2

כי יפלא means, if he expressly states by an utterance of his mouth (cf. Rashi on Leviticus 22:21).

כי יפלא, he will set aside. The word means something similar to the word מפרש, in the sense of spelling out details. Anyone making a vow has to clearly define what he is vowing to do.

איש כי יפלא נדר, “if a man articulates a vow, etc.” According to Nachmanides this paragraph is also conceptually linked to the admonitions we have read in chapter 26. It was told to Moses already at Mount Sinai [see commentary at the beginning of chapter 25. Ed.] Seeing that part of this chapter deals also with the Jubilee year legislation inasmuch as it is relevant to redeeming matters declared sacred as a result of vows made, the thread has not been broken ever since the beginning of chapter 25, and the additional aspects of the legislations dealing with vows in which man declares someone or his equivalent sacred in terms of that person or object’s valuation only rounds out that section of legislation. To confirm this, the Torah, at the end of our chapter writes once more that all the aforementioned commandments were commanded by G’d to Moses to the Children of Israel at Mount Sinai [already. Ed.] What follows from now on was told Moses in the Tabernacle.