The word כי is very short, but very complicated. The reason is that it has many different meanings. You can only really figure out what it means from its context. The Talmud quotes Reish Lakish, a scholar who lived in the Land of Israel in the 3rd century, who famously said:
כי משמש בד’ לשונות: אי, דלמא, אלא, דהא
The word כי has 4 meanings: ‘If’, ‘Perhaps’, ‘Rather’ and ‘For’. [Gittin 90a]
Rashi gives a different range of means for the word כי. He writes:
Kee means ‘IF’ – as in the verse:
‘כי יקרא קן צפור’ / ‘If you come across a birds nest’ / [Deut 22:6]
It means ‘RATHER’ – as in the verse:
‘לא כי ברחוב נלין’ / ‘No – rather we will sleep in the street’ / [Gen 19:2 ]
It means ‘LEST’ – as in the verse:
‘כי תאמר בלבבך רבים הגויים האלה’ / ‘Lest you say – these nations are more numerous than I … Fear them not / [Deut 7: 17]
It means ‘WHEN’ – as in the verse:
‘והיה כי יביאך ה’ אלוקיך אל הארץ’/ ‘It shall come to pass when the Lord your God brings you to the Land’ / [Deut 7: 1]
It is even more complicated than this. Carl M. Follingstad published a 700-page book entitled Deictic Viewpoint in Biblical Hebrew Text: A Syntagmatic and Paradigmatic Analysis of the Particle כי (kî). He delineates over a dozen different nuances of meaning for this word!
The main problem you face when you come across this word is deciding which of the meanings is being used. This is frequently ambiguous, and can lead to competing interpretations of a text.
Consider a well know verse from the Book of Deuteronomy:
For a man is like the tree of the field / כִּי הָאָדָם עֵץ הַשָּׂדֶה / [Deut 20:9].
The Israeli poet Natan Zach’s poem ‘The Tree of the Field’ , made famous in the version performed Shalom Hanoch, is based on this verse.
[Embedded YouTube Clip: http://www.youtube.com/watch?v=GTjYHa4r_CQ]
For the man is like the tree of the field;
Like the tree the man grows up.
Like the man, the tree also gets uprooted,
And I surely do not know where I have been and where I will be,
like the tree of the field.
This beautiful song is, however, based on a misunderstanding of the verse in the Torah. The word כי in this verse doesn’t mean ‘For’ [For a man is like the tree of the field], but rather ‘Perhaps’ [Is the tree of the field like a man?]. The Torah wants to say that we need to show compassion towards trees because they are not like us. The full verse reads: ‘Is the tree of the field a man, who can run away from you in a siege?’ It is precisely because the trees aren’t like us that we have to protect them and take responsibility for their wellbeing.
Language is the art of communicating meaning using words. A good reader needs to be sensitive to more than words; frequently the real meaning is found in the context, hidden between the lines, in the things that are not said. Perhaps no word tests our skill of reading the wider context of a word more than the short word כי.
Rabbi Chaim Weiner
My Hebrew Word thanks the World Zionist Organisation and Masorti Olami for their support of this Project.