In addition to Nigel's answer. We are cautioned to be sober and vigilant, and to put on the whole armour of God as a guard against Satan.
Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour (1 Peter 5:8)
Put on the whole armour of God, that ye may be able to stand against the wiles of the devil... Above all, taking the shield of faith, wherewith ye shall be able to quench all the fiery darts of the wicked. (Ephesian 6:11-16)
Judas did none of that, but allowed himself to continue in covetousness. We do not stay the same, with each ray of grace, we either accept it and become more like Jesus, or deny it and become more like Satan. Judas continued in his sin until Satan presented him an overmastering temptation.
Interesting, Satan had once used Peter also. It shows how easily we can become prey if we are not prayerful. However, Peter repented and eventually became a better man because of it.
Then Peter took him [Jesus], and began to rebuke him, saying, Be it far from thee, Lord: this shall not be unto thee. But he turned, and said unto Peter, Get thee behind me, Satan: thou art an offence unto me: for thou savourest not the things that be of God, but those that be of men. (Matthew 16:22-23)
And Peter remembered the words of Jesus, who said unto him, Before the cock crows, you shall deny me three times. And he went out, and wept bitterly. (Matthew 26:75)
On the other hand, those who refuse to repent will become like the condition of those belonging in Babylon in the last days.
And he cried mightily with a strong voice, saying, Babylon the great is fallen, is fallen, and is become the habitation of devils, and the hold of every foul spirit, and a cage of every unclean and hateful bird. (Rev 18:2)