The Holy Family plays hide and seek for three days.

 

After the festival of Passover in Jerusalem in which the Holy Family was in attendance, with friends and family from Nazareth. Unbeknownst to the Blessed Virgin Mary and St. Joseph, Jesus went to the Temple and sat among the Doctors and Lawyers of the Temple listening to them and asking and answering questions in turn. The doctors and lawyers were astounded by His wisdom. Knowing the whole story, unlike the Doctors and Lawyers, that is knowing that Jesus is God, it is unsurprising that they were astonished by His wisdom, since God is the fullness of all perfections, and is perfectly wise. But I guess that's a bit of a spoiler alert to the Judaic doctors and lawyers of the temple.

After the Blessed Virgin Mary and St. Joseph thought they left all together, they realized that Jesus had stayed in Jerusalem, and as any parent would they were distraught at realizing their kind isn't with them or their trusted friends and family. So they hurried back, and probably set a land speed record for getting to Jerusalem on foot or donkey. Three days have passed by this point, they probably hoped that someone in the Temple had seen Jesus, but lo and behold Jesus is in the Temple, His Father's House. This goes to show that we can always find Jesus in His Father's House waiting for us to come to Him. In every Catholic Church is the Tabernacle, and every day of the year (except Holy Saturday of Holy Week), Jesus is there in the tabernacle, waiting for you to come visit Him. 

The fruit of this Mystery is Piety. If you want to read what it means to be pious I do not recommend the Meno dialog with Socrates, its a bit dry and no clear definition. But if you want to know Piety and to become pious yourself, well all you have to do is go be with our Lord. He is Piety, and if we imitate Him in all things and become like Him, He and His Father and the Holy Ghost dwell within us, and we become pious. 

The Scriptural Rosary is:

1. The Fifth Joyful Mystery: Finding Jesus in the Temple
1. Pater Noster ...
2. And his parents went every year to Jerusalem, at the solemn day of the pasch, And when he was twelve years old, they going up into Jerusalem, according to the custom of the feast, (Luke 1:41-42)
1. Ave Maria … 
3. And having fulfilled the days, when they returned, the child Jesus remained in Jerusalem; and his parents knew it not. (Luke 1:43)
1. Ave Maria … 
4. And not finding him, they returned into Jerusalem, seeking him. And it came to pass, that, after three days, they found him in the temple, (Luke 1:45-46a)
1. Ave Maria … 
5. sitting in the midst of the doctors, hearing them, and asking them questions. (Luke 1:46b)
1. Ave Maria … 
6. And all that heard him were astonished at his wisdom and his answers. (Luke 1:47)
1. Ave Maria … 
7. And seeing him, they wondered. And his mother said to him: Son, why hast thou done so to us? behold thy father and I have sought thee sorrowing. (Luke 1:48)
1. Ave Maria … 
8. And he said to them: How is it that you sought me? did you not know, that I must be about my father's business? (Luke 1:49)
1. Ave Maria … 
9. And they understood not the word that he spoke unto them. (Luke 1:50)
1. Ave Maria … 
10. And he went down with them, and came to Nazareth, and was subject to them. And his mother kept all these words in her heart. (Luke 1:51)
1. Ave Maria … 
11. And Jesus advanced in wisdom, and age, and grace with God and men. (Luke 1:52)
1. Ave Maria … 
12. O My Jesus ...
13. Gloria Patri ...