Scripture:

Mark 4:30-32
30 And He said, "How shall we picture the kingdom of God, or by what parable shall we present it? 
31 "It is like a mustard seed, which, when sown upon the soil, though it is smaller than all the seeds that are upon the soil, 
32 yet when it is sown, it grows up and becomes larger than all the garden plants and forms large branches; so that THE BIRDS OF THE AIR can NEST UNDER ITS SHADE."
NASU


Thoughts:

Ever feel as though your life or ministry are insignificant?  I think probably all of us do at one time or another.  We ask ourselves questions like, does it really matter if I do my part?  Is it having any impact?  Will anything I do outlast me in time?  Though in truth we have nothing to despair over as believers, we may sometimes find ourselves flirting with it, nonetheless.

But this passage stands in contrast to fatalistic thinking.  Look at the impact a tiny seed can have! (verse 32)  From a tiny metaphorical seed, the kingdom of God would grow.  Commentators interpret this "seed" as the apostles and first believers in Christ.  They were few in number, but look to what size the church has grown throughout the centuries.

In the same way, on a personal level, a simple life of godly character and relational evangelism and discipleship, can have a tremendous impact for the Lord.  The seeds we plant in the lives of others will bring an abundant harvest as the Lord cares for the receivers, and makes them grow, as Paul recounted of his own ministry:

1 Corinthians 3:5-6
5 What then is Apollos? And what is Paul? Servants through whom you believed, even as the Lord gave opportunity to each one. 6 I planted, Apollos watered, but God was causing the growth.
NASU