The Beatific Vision is the Blessed Vision of God that our divine Savior promised in these words, "Blessed are the pure in heart: for they shall see God." (Mat 5:8)
In Hebrews, we read no one sees the Lord without holiness: "Pursue peace with all men, as well as holiness, without which no one will see the Lord." (Heb 12:14). In St. John the Apostle's First Epistle, we learn that we shall be like Him, when we see Him as He Is, "Beloved, we are now children of God, and what we will be has not yet been revealed. We know that when Christ appears, we will be like Him, for we will see Him as He is." (1 Jn 3:2). Again in the Apocalypse, it is said, "They will see His face, and His name will be on their foreheads." (Rev 22:4). So the blessed see God Face to Face. Our Lord Himself said, "if thou wouldest believe, thou shouldest see the glory of God" (Jn 11:40).
The Catholic Encyclopedia explains: "The immediate knowledge of God which the angelic spirits and the souls of the just enjoy in Heaven. It is called "vision" to distinguish it from the mediate knowledge of God which the human mind may attain in the present life. And since in beholding God face to face the created intelligence finds perfect happiness, the vision is termed "beatific".[1]