Naaman is cleansed in the Jordan River because of God's mercy. We too are cleansed in the river of God's mercy flowing from the wounds of Christ to bring mercy to the world.
2 Kings 5:14-17
Naaman went down and plunged into the Jordan seven times
at the word of Elisha, the man of God.
His flesh became again like the flesh of a little child,
and he was clean of his leprosy.
Naaman returned with his whole retinue to the man of God.
On his arrival he stood before Elisha and said,
"Now I know that there is no God in all the earth,
except in Israel.
Please accept a gift from your servant."
Elisha replied, "As the LORD lives whom I serve, I will not take it;"
and despite Naaman's urging, he still refused.
Naaman said: "If you will not accept,
please let me, your servant, have two mule-loads of earth,
for I will no longer offer holocaust or sacrifice
to any other god except to the LORD."