“The heart itself is but a small vessel, yet dragons are there, and there are also lions; there are poisonous beasts and all the treasures of evil. But there too is God, the angels, the life and the kingdom, the light and the apostles, the heavenly cities and the treasuries of grace—all things are there.”
(St. Macarius of Egypt (300-391) a Coptic Christian monk and hermit)
Our hearts hold both options of good and evil but with the Baptism of the Holy Spirit we should be much more concentrated on the light, the Kingdom, Jesus and a pure and strong life. To the pit with dragons, beasts and lions that try to attack us and split or destroy our hearts. The power of the God is greater than the power of the enemy.
Otherwise… we are in heart attack and failure mode.
“Do not let your hearts be troubled. You believe in God; believe also in me.” Jesus