This was an awesome being of power, so great that ordinarily strong, valiant men were so frightened that they ran. Yet something withstood this great being to his face and kept him from getting to Daniel for three full weeks. We cannot even begin to imagine the titanic struggle that went on between, say, Gabriel and this other being. There must have been such an awesome wrestling match as men have never been witness to.
Whatever it was that withheld Gabriel from getting to Daniel must have been awfully powerful. Notice too that this great struggle was going on without Daniel even being aware of it. Somehow a malignant demon tried to thwart Daniel's prayer from being answered.
But it was answered because, in verse 13, "Michael, one of the chief princes, came to help me, for I had been left alone there with the kings of Persia." It was not until two of them ganged up on this other being—two great, mighty archangels to subdue the other. The logical conclusion would almost have to be that the king of Persia mentioned here was none other than Satan.
This section in Daniel 10 really contains a great deal of encouragement. We can understand why the apostle Paul and the psalmist wrote that the angels are ministering spirits. They are ministering to the heirs of salvation. They are protecting us! They are standing between us and possible annihilation! We do not know how many times an angel has intervened to save our lives, to deflect the power of these malignant beings from us. It has happened repeatedly in some cases, not just in dramatic interventions, but where an intervention took place of which we were not even aware.
John W. Ritenbaugh
Satan (Part 1)