You are going to have to be prepared to receive a heck of a lot of different views since it involves a verse in Scripture that may be interpreted widely.
For a start I am not sure what you mean by the expression "system of things" That is Watchtower-speak, which is another way of saying it is Freddy Franz-speak, since this was one of his favourite expressions. When I ask a WT follower for a definition, I get a series of meaningless phrases all pointing suspiciously toward the definition of "world" yet they insist that it is something different. The strange thing is that no one asked me for a definition when I was a WT follower, so like everyone else I assumed Franz had a correct "translation"
The actual term used in the Greek is "Aion" simply meaning a time period, an age. 2Cor 4:4 describes Satan as the "god of this age" or the "god of the times in which we are currently living". The extent of his influence is limited and is described for us in this very verse.His power evidently made possible on the sufferance of God, lies in his ability to "blind the minds of people so that the illumination that comes from the Gospel message of Christ - not the WTS, not Jehoover, not any organization, not any GB - will not shine through. Paul states quite finally in 2Cor 4:5] that we [ie True Christians] are preaching NOT OURSELVES, ie the WTS, not jehoover, not any GB to be loyal to, but Christ as Lord. Could it be that some J document somewhere will reveal that Kurios listed here is in fact YHWH? [See 1Cor 12:3 in J14]
The WTS makes a great play about Satan ruling this "world" as if he controls the nations. It is naturally in their interest to push this view, because it encourages their acolytes to remain exclusively bound to their apron strings. If their acolytes spent any amount of time deciding whom to vote for, or if they went to union meetings, it's that much time taken away from their attention that they might give to the organization. Like the master they serve, the WTS leadership has an arrogant and demanding posture they adopt with their followers. It is to them, and them alone you must bend the knee, and touch the forelock.
There is certainly nothing in Scripture to indicate such a blasphemous view of Satan's power.. God is in control of the nations. He always was and He always will be. Ps 47:8,9 makes this plain. "God is the King of the earth He reigns over the nations" Satan's ability to influence minds may indeed extend to those rulers of the world whom he considers fitting subjects.
And Rom 13:1 makes it plain that the Christian has a social obligation towards the governments of the world, Why? Because, Paul says, those governments are "BY" Greek - Hupo - God. The pompous "translation" made by Freddy Franz here reads like a lawyer's dream "Stand placed in their relative positions by'' 37 letters in 7 separate words to render a simple three letter word in Greek.
The world Satan actually controls is described for us in Eph 6:12: "The world of this darkness, [not the world of the nations] the wicked spirt forces in the spirit realm" It is this demonic realm, with it's occult practices, and which the WTS evidently embraces, in that it is in contact with the spirits of the dead ex-leaders of the organization, that the True Christian must contend with.
OK... Having said that what about the incident regarding the Temptation of Christ? How could Satan promise to give Christ the nations of the world if he didn't control them. It is because he is a liar, remember. Like a snake oil salesman, or a con artist, satan was trying to sell something he did not have to sell in the first place. Remember Christ has made one definitive statement regarding Satan: "There is NO truth in him" [Jo 8:44] It is not that he tells the truth sometimes, or maybe or possibly. It simply is that he never, ever tells the truth. So it is simple really. Always believe the opposite of what he says. If he says you will live, it means you will die. If he says he will give you something he never will, because he doesn't have it to give. The blandishments of Satan, persuasive to the physical eyes, are in fact fatal.
What influence Satan exacted in the OT "aion" or time period is not revealed. The revelation of a devil in the Hebrew OT is amorphous at best, and subject to several variant readings. The demonic authority of Satan is peculiarly a NT teaching. And it there that we need to turn if we want to know his operations.
As a free people, unfettered by bonds of darkness exacted by those making extraordinary claims about being the exclusive spokesmen of God, we need to ensure that the "god" they represent does not tell lies, is neither fraudulent, nor a flimflam mirage.
Cheers
