The person behind this illumination is the Holy Spirit.  Just prior to His crucifixion, Christ promised to send the Holy Spirit, who would illumnate both unsaved people (John 16:8-11 And when he is come, he will reprove the world of sin, and of righteousness, and of judgment: Of sin, because they believe not on me; Of righteousness, because I go to my Father. and you see me no more; Of judgment, because the prince of this world is judged.  The Spirit convinces of the fact of sin, that we have done so and so; of the fault of sin, that we have done ill in doing so; of the folly of sin, that we have acted against right reason, and our true interest; of the filth of sin, that by it we are become odious to God; of the fountain of sin,  the corrupt nature; and lastly, the fruit of sin, that the end thereof is death.  Of Christ's righteousness communicated to us for our justification and salvation; that everlasting righteousness which Messiah was to bring in. The Spirit will convince men of this righteousness. Having by convictions of sin shown them theeir need of a righteousness, lest this should drive them to despair, he will show them where it is to be had, and how they may, upon their believing,, be acquitted from guilt, and accepted as righteous in God's sight.  The devil, the pince of this world, was judged, was discovered to be a great deceiver and destroyer, and as such judgment was entered against him, and exection in part done.  He was cast out of the Gentile world when his oracles were silenced and his altars deserted, cast out of the bodies of many in Christ's name, which miraculous power continued long in the church, he was cast out of the souls of people by the grace of God working with the gospel of Christ; he fell as lightening from heaven.) and Christians (John 14:26 But the comforter, which is the Holy Ghost, whom the Father will send in my name, he will teach you all things, and bring all things to your rememberance, whatsoever I have said unto you.  On whose account he should be sent: "The Father will send him in my name: that is, for my sake, at my special instance and request:" or," as my agent and representative." He came in his Father's name, as his ambasador: the Spirit comes in his name, as resident in his absence, to carryb his undertaking, and to ripen things for his second coming. Hence he is called the Spirit of Christ, for he pleads his cause, and does his work.,  John 16: 13, 14  Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whosoever he will hear, that will he speak: and he will show you things to come.  He will glorify me: for he will receive of mine, and will show it unto you. The Spirit spoke of the apostasy of the latter times. John, when he was in the Spirit had things to come shown him in vision. Now this was a great satisfaction to their own minds, and of use to them in their conduct, and was also a great confirmation of their mission. Jansenius has a pious note upon this: We should not grudge that the Spirit does not show us things to come in this world, as he did to the apostles; let it suffice that the Spirit in the word hath shown us things to come in the other world, which are our chief concern.  (The Spirit undertook to glorify Christ. Even the sending of the Spirit was the glorifying of Christ. God the Father glorified him in heaven, and the Spirit glorified him on earth. It was the honour of the Redeemer that the Spirit was both sent in his name and sent on his errand, to carry on and perfect his undertaking. All the gifts and graces of the Spirit, all the preaching and all the writing of the apostles, under the influence of the Spirit, the tongues, and miracles, were to glorify Christ.).