Often, when reading a Biblical commentator, half the work is figuring out their motivation. The verse says what it says, and the commentator observes something about that verse. This can be a feature, or it could be an interpretation of events. Famously, what is bothering Rashi — though often those who ask the question misunderstand what “bothers” him and therefore answer the question incorrectly.
Here is an obvious Chizkuni. It is so obvious that you have to wonder why he bothers saying it. The verse in question is Bemidbar 14:34:
בְּמִסְפַּ֨ר הַיָּמִ֜ים אֲשֶׁר־תַּרְתֶּ֣ם אֶת־הָאָ֘רֶץ֮ אַרְבָּעִ֣ים יוֹם֒ י֣וֹם לַשָּׁנָ֞ה י֣וֹם לַשָּׁנָ֗ה תִּשְׂאוּ֙ אֶת־עֲוֺנֹ֣תֵיכֶ֔ם אַרְבָּעִ֖ים שָׁנָ֑ה וִֽידַעְתֶּ֖ם אֶת־תְּנוּאָתִֽי׃
You shall bear your punishment for forty years, corresponding to the number of days—forty days—that you scouted the land: a year for each day. Thus you shall know what it means to thwart Me.
and Chizkuni writes, according to Eliyahu Munk’s translation:
Indeed, if you look at the verse, the first word is בְּמִסְפַּ֨ר, and the bet has a dagesh kal in it. This is entirely expected, since the letters beged kefet at the start of a word are marked with that dagesh. The only exception is if, sometime, the preceding word ended with a vowel sound (like ehevi, אהוי) and there’s a conjunctive trup accent. Yet, this is also the beginning of a verse, so there’s a disjunctive trup accent, the silluq. Anyway, the previous word is בַּמִּדְבָּֽר׃, which ends in a resh, which is a consonant.
This is so blindingly obvious that Chizkuni would not say this. Why should he say this? What could possibly motivate him?
In addition, note that the Chizkuni text does not have nekudot, so it just says בבית, not בבּית. The idea that it the dagesh at play is conjecture.
Here is the alternative, from the perspective of what could motivate Chizkuni. That pasuk again is:
בְּמִסְפַּ֨ר הַיָּמִ֜ים אֲשֶׁר־תַּרְתֶּ֣ם אֶת־הָאָ֘רֶץ֮ אַרְבָּעִ֣ים יוֹם֒ י֣וֹם לַשָּׁנָ֞ה י֣וֹם לַשָּׁנָ֗ה תִּשְׂאוּ֙ אֶת־עֲוֺנֹ֣תֵיכֶ֔ם אַרְבָּעִ֖ים שָׁנָ֑ה וִֽידַעְתֶּ֖ם אֶת־תְּנוּאָתִֽי׃
You shall bear your punishment for forty years, corresponding to the number of days—forty days—that you scouted the land: a year for each day. Thus you shall know what it means to thwart Me.
Literally, בְּמִסְפַּ֨ר הַיָּמִ֜ים means “in the number of days”. However, in context, it means, as rendered above, “corresponding to the number of days”. Most strictly, we should expect the letter kaf, kemispar hayamim, “like the number of days” to express it.
So, Chizkuni is observing that בְּמִסְפַּ֨ר begins with a bet, not a kaf, despite meaning “like the number of days.” And that kaf can carry this meaning.
This is good to read. Thanks