We know that there are three comings of the Lord. The third lies between the other two. It is invisible, while the other two are visible… In the first coming he was seen on earth, dwelling among men; he himself testifies that they saw him and hated him. In the final coming all flesh will see the salvation of our God, and they will look on him whom they pierced… 

In case someone should think that what we say about this middle coming is sheer invention, listen to what our Lord himself says: If anyone loves me, he will keep my word, and my Father will love him, and we will come to him. There is another passage of Scripture which reads: He who fears God will do good, but something further has been said about the one who loves, that is, that he will keep God’s word. Where is God’s word to be kept? Obviously in the heart, as the prophet says: I have hidden your words in my heart, so that I may not sin against you.

Keep God’s word in this way. Let it enter into your very being, let it take possession of your desires and your whole way of life. Feed on goodness, and your soul will delight in its richness. Remember to eat your bread, or your heart will wither away. Fill your soul with richness and strength…

If you keep the word of God in this way, it will also keep you. The Son with the Father will come to you. The great Prophet who will build the new Jerusalem will come, the one who makes all things new. This coming will fulfill what is written: As we have borne the likeness of the earthly man, we shall also bear the likeness of the heavenly man. Just as Adam’s sin spread through all mankind and took hold of all, so Christ, who created and redeemed all, will glorify all, once he takes possession of all.

St. Bernard of Clairvaux
Sermo 5, In Adventu Domini, 1-3:
Opera Omnia, Edit. Cisterc. 4 {1966}, 188-190.