Matthew 13:31-32 - Another parable He put forth to them, saying: “The kingdom of heaven is like a mustard seed, which a man took and sowed in his field, which indeed is the least of all the seeds; but when it is grown it is greater than the herbs and becomes a tree, so that the birds of the air come and nest in its branches.”
We just talked about this at women's Bible study! It's about our faith. You know, it can be as small as a mustard seed. And as Sandra pointed out, it's not so much about how big our faith is, but how strong it is and are being able to see how big our God is in any situation.
Our faith in God and His Word and believing all the Word proclaims takes faith. We cannot see God, Jesus or the Holy Spirit but they are here. It takes faith to believe that.
A mustard seed is the smallest of seeds but it can grow to be like a tree. I know we have wild mustard in the woods (not necessarily this same species) around us and it must be kept in check or it will take over. It's roots are strong and deep and when it's in the garden it takes work to dig it out. If we have faith like this bitty mustard seed it will grow roots into our spirits (strength). If we have this faith it is not something that can easily be plucked out...but we need to be continually in the Word to receive the sustenance to keep this faith alive.
The kingdom of heaven will be filled with believers who have held to that faith. It is a good place to be, in this faith, nesting in the peace, hope and joy that God supplies through faith in Him, despite troubles in life we will encounter.
Luke 17:5-6 - And the apostles said to the Lord, “Increase our faith.” So the Lord said, “If you have faith as a mustard seed, you can say to this mulberry tree, ‘Be pulled up by the roots and be planted in the sea,’ and it would obey you."