Musar zu Bereschit 6:4

We must appreciate that when G–d created different worlds, He named, i.e. formed and defined them by means of a combination of the letters of the alphabet. Our sages say that Betzalel understood the mystery of the combinations of all of these letters which make up the names [definitions] of all things found in this world (Berachot 55 based on the word שם in Exodus 35,30). Early man, who was still בצלם אלוקים, was still able to understand the significance of the names of G–d, and used these names to serve Him in holiness and love in order to cleave to Him. This condition came to an end with the generation of Enosh, as we have explained earlier based on Bereshit Rabbah. When we read in Genesis 4,26 that during the lifetime of Enosh אז הוחל לקרא בשם ה', "then one began to profane the name of the Lord," the meaning is that people no longer used His Name in holiness but desecrated it. The expression הוחל indicates something that is profane, חולין. This situation continued until the advent of the deluge. When the Torah speaks about המה הגבורים אשר היו מעולם אנשי השם, "they were the heroes of old, men of the "Name" (Genesis 6,4), this means that these people used the name of G–d to manipulate the universe, as described in the Zohar, Sullam edition page 209. The expression אנשי השם in Genesis, and the expression ויקוב את השם in Leviticus 24,11, where the Torah refers to the blasphemer, suggests a similar misuse of the Holy Name of G–d in both instances. It was the ability of these people to use G–d's name in order to manipulate it that made them disregard the warnings of an impending deluge. All this is described at greater length in the Zohar. We find that the people of Jerusalem are described by the prophet Ezekiel 12,19 as also having displayed misplaced optimism concerning the prophecies of doom by Jeremiah. The people's very knowledge of G–d's name was what misled them. This is the justification for the reference in Ezekiel to these people as "dwellers in ruins" when in fact they were still dwelling in Jerusalem.