He replied, “Because you have so little faith. Truly I tell you, if you have faith as small as a mustard seed, you can say to this mountain, ‘Move from here to there,’ and it will move. Nothing will be impossible for you.”
I don't believe He was speaking of a literal mountain, but it was a statement that with the power of God we have the ability to overcome any obstacle or challenge that occurs in our life.
The words we speak are not only responsible for determining how people respond to us, but they can guide our relationship with God. Matthew 12:34 - 37 is a perfect example of how words can postively or negatively impact our lives.
34 You brood of vipers, how can you who are evil say anything good? For the mouth speaks what the heart is full of. 35 A good man brings good things out of the good stored up in him, and an evil man brings evil things out of the evil stored up in him. 36 But I tell you that everyone will have to give account on the day of judgment for every empty word they have spoken. 37 For by your words you will be acquitted, and by your words you will be condemned.”
These scriptures bring up some things to consider every time we open our mouths. In that, our mouth will convey what is truly in our hearts and that a heart that follows God's way will produce goodness and blessing, if you are not living by His will you will produce evil. When we go before God in judgement we must account for EVERY word spoken.
When speaking we must keep some scriptures in mind, such as Colossians 4:6.
6 Let your conversation be always full of grace, seasoned with salt, so that you may know how to answer everyone.
We should always speak from a God-fearing mindset and if we keep God's word in mind and heart we will be able to talk to anyone about Him. We should also consider Proverbs 8:6-9.
6 Hear, for I will speak noble things,and from my lips will come what is right,
7 for my mouth will utter truth;wickedness is an abomination to my lips.
8 All the words of my mouth are righteous;there is nothing twisted or crooked in them.
9 They are all straight to him who understands,and right to those who find knowledge.
We should speak honoring God with truth and avoid lies or deciet.
We should also always keep in mind the things that could hinder our relationship with God such as vanity, profanity, ungodly, judging, or gossiping about others.
2 Timothy 2:16
16 But shun profane and vain babblings: for they will increase unto more ungodliness
3 The Lord shall cut off all flattering lips, and the tongue that speaketh proud things
11 Brothers and sisters, do not slander one another. Anyone who speaks against a brother or sister[a] or judges them speaks against the law and judges it. When you judge the law, you are not keeping it, but sitting in judgment on it.