What have I stored up in my heart?

No good tree bears bad fruit, nor does a bad tree bear good fruit.
Each tree is recognized by its own fruit.
People do not pick figs from thornbushes, or grapes from briers.
The good man brings good things out of the good stored up in his heart, and the evil man brings evil things out of the evil stored up in his heart.
For out of the overflow of his heart his mouth speaks.
Luke 6:43-45

Was reflecting on this passage and several thoughts struck me.

• The quality of fruit is consistent with its source/parent. Good tree = Good fruit. Good fruit = Good tree. My actions will either bless or betray me. And others.
• Good and evil are stored up in the heart. They don't leak or deplete. They keep filling up till the container is full and overflows. For good or bad. Imagine a full petrol tank, a bank account will lots of zeroes (in the right places), a water tank after a rainy spell.
• Our speech reflects what's been quietly building up in our hearts. Sometimes, one remark is all it takes to reveal what's really important to us. Thoughtless words that hurt and demean could be traced back to negative thinking, wrong attitudes, a self-centred lifestyle, stimulation that entertains us but does not improve us. Trashy books, movies and TV shows. Acquaintances who pursue materialism, instant gratification of the senses and the attitude that you have only one life and you may as well enjoy it to the full, who cares about others and what they think. In contrast, words that help and heal and point someone to the straight and narrow path may well be the fruit of years of right thinking, right action, wholesome sources of stimulation, time spent reflecting on what is good and pure, a desire to be holy, a consistent walk with God.
  

Let us be mindful of what we say, because our words reveal the true us beneath our masks of politeness and convention.