Matthew 6 addresses treasures in heaven in Matthew 6:19–21, part of the Sermon on the Mount.
19 Lay not up for yourselves treasures upon earth, where moth and rust doth corrupt, and where thieves break through and steal: 20 But lay up for yourselves treasures in heaven, where neither moth nor rust doth corrupt, and where thieves do not break through nor steal: 21 For where your treasure is, there will your heart be also.
The passage contrasts treasures laid up on earth — which moth and rust corrupt and thieves steal — with treasures laid up in heaven, and closes with the statement that the heart follows the treasure. Full chapter: Matthew 6.