We might consider that the Virgin Mary is like this book, sealed with seven seals, that Saint John the Evangelist saw in the Revelation, and which could only be opened by the Lamb (Rev 5:5).
The seven seals are the seven gifts of the Holy Spirit that the Virgin Mary fully possesses, more than any other creature. We can also understand them as the seven privileges that she enjoys.
In the first, she was chosen by God from all eternity as the first-born of all the creatures. In the second, she conceived in her womb and in her flesh the Word and his humanity, which he received from her most pure blood. In the third, she sanctified Saint John by her words, by virtue of the incarnate Word in her most pure womb. In the fourth, after she had given birth to Jesus, she remained a virgin. In the fifth, the Son of God himself was subjected to her, humble and obedient. In the sixth, after her death her body did not know corruption. In the seventh, she was placed at the right hand of her Son.
If, after we die, we want to enter into the blessed Kingdom of Heaven, we must strive right now to perfection, practice humility, patience, charity, and all the other virtues. Let us exert ourselves to do so.