How does one call Chachmah his sister?
Rashi: Draw it close to you.
Malbim: Closeness to a sister is from birth. Closeness to a Moda is from choice. Man does not find the laws of Chachmah by himself, only if Hashem gives them to him, just like love of a sister is from Elokim.
What is "Moda"?
Rashi: It is a relative, like "Bo'az Modatanu" (Rus 3:2). I.e. bring [Chachmah] close to you always.
Malbim: All powers that are the subjects of Chachmah are found in man's Nefesh from its formation, just like closeness of a sister is from birth. However, Binah (understanding a matter amidst another matter) man begets it from his Da'as. Therefore, it says "u'Moda la'Binah Sikra" - like a Moda, to whom one chose to be close.