Twelve Memorial Stones.

When all the nation had finished passing over the Jordan, the Lord said to Joshua, “Take twelve men from the people, from each tribe a man, and command them, saying, ‘Take twelve stones from here out of the midst of the Jordan, from the very place where the priests' feet stood firmly, and bring them over with you and lay them down in the place where you lodge tonight.’” Then Joshua called the twelve men from the people of Israel, whom he had appointed, a man from each tribe. And Joshua said to them, “Pass on before the ark of the Lord your God into the midst of the Jordan, and take up each of you a stone upon his shoulder, according to the number of the tribes of the people of Israel, that this may be a sign among you. When your children ask in time to come, ‘What do those stones mean to you?’ then you shall tell them that the waters of the Jordan were cut off before the ark of the covenant of the Lord. When it passed over the Jordan, the waters of the Jordan were cut off. So these stones shall be to the people of Israel a memorial forever.” (Joshua 4: 1 to 7)

Before leaving Egypt, God commanded Moses to follow the Feast of Unleavened Bread as described below.

Unleavened bread shall be eaten for seven days; no leavened bread shall be seen with you, and no leaven shall be seen with you in all your territory. You shall tell your son on that day, ‘It is because of what the Lord did for me when I came out of Egypt.’ And it shall be to you as a sign on your hand and as a memorial between your eyes, that the law of the Lord may be in your mouth. For with a strong hand the Lord has brought you out of Egypt. You shall therefore keep this statute at its appointed time from year to year. (Exodus 13: 7 to 10)

It's understandable why the unleavened bread prior to their hasty journey to flee Egypt, so that they could leave fast without waiting for their bread dough to rise (leaven). Also, without the yeast symbolized the Israelites to leave the sin and impurity behind.

As for after crossing the river Jordan, God commanded Joshua to take twelve stones, one for each tribe, from the river where the priests' feet stood firmly and bring them over with them and lay them down in the place where they lodged that night. Joshua also set up twelve stones in the Jordan where the priests bearing the ark of the covenant had stood. So, the twelve Memorial Stones not only served as a memorial, but also a witness to receive the rest that Joshua had promised. To receive the rest, they needed to follow God's righteousness, the ark, to dip in the water and leave their past behind. It's as what was described in the Bible below.

In those days John the Baptist came preaching in the wilderness of Judea, “Repent, for the kingdom of heaven is at hand.” For this is he who was spoken of by the prophet Isaiah when he said, “The voice of one crying in the wilderness: ‘Prepare the way of the Lord; make his paths straight.’”

Now John wore a garment of camel's hair and a leather belt around his waist, and his food was locusts and wild honey. Then Jerusalem and all Judea and all the region about the Jordan were going out to him, and they were baptized by him in the river Jordan, confessing their sins. (Matthew 3: 1 to 6)

So, John the Baptist who was living in the wilderness symbolized how the Israelites were wandering in the wilderness. The baptismal in the river Jordan reminded them how God led their ancestors to cross the Jordan to enter God's rest. It is also described in the Bible as below.

Then Jesus came from Galilee to the Jordan to John, to be baptized by him. John would have prevented him, saying, “I need to be baptized by you, and do you come to me?” But Jesus answered him, “Let it be so now, for thus it is fitting for us to fulfill all righteousness.” Then he consented. And when Jesus was baptized, immediately he went up from the water, and behold, the heavens were opened to him, and he saw the Spirit of God descending like a dove and coming to rest on him; and behold, a voice from heaven said, “This is my beloved Son, with whom I am well pleased.” (Matthew 3: 13 to 17)

Jesus was sinless. Yet he was baptized to fulfill God's righteousness for the people of Israel to receive the rest as they were crossing the river Jordan. Not only for them but also for those who are saved by grace as described in the Bible below.

And he said to them, “Go into all the world and proclaim the gospel to the whole creation. Whoever believes and is baptized will be saved, but whoever does not believe will be condemned. And these signs will accompany those who believe: in my name they will cast out demons; they will speak in new tongues; they will pick up serpents with their hands; and if they drink any deadly poison, it will not hurt them; they will lay their hands on the sick, and they will recover.” (Mark 16: 15 to 18)

So, by being baptized with faith, we would be ensured with salvation and heavenly blessings too. Immanuel.