This is so that we won’t be taken advantage of by Satan, because we are well aware of his schemes.
lest Satan should get an advantage of us: for we are not ignorant of his devices.
To keep Satan from getting the advantage over us; for we are not ignorant of his wiles and intentions.
that no advantage may be gained over us by Satan: for we are not ignorant of his devices.
so that we would not be circumvented by Satan. For we are not ignorant of his intentions.