GEN612 The fate of the Generation of the Flood was sealed only over theft, as (this verse) says “The end of all flesh has come before Me, for the earth has become filled with larceny.”  Although the sin of illicit relations is graver than that of theft, the punishment of theft has the quality of bringing the day of catastrophe closer and speeding up the unfolding of [calamitous] future events.  They also said, Ecclesiastes Rabbah 1:13, “In a ‘se’ah [a measure of volume] filled with sins – there is none among them that prosecutes as much as theft.’”  [Translated in TZADIK 153 as “In a measure full of sins there is none more incriminating than that of theft.”]  GATES 195