Jeremiah 13:1-11
Psalm 78:55-63
Matthew 13:31-35
The imagery of the one who loves God as being like a tree is found elsewhere in Scripture; the best example is probably in the Psalms. There, the book itself begins with a description of one whose “delight is in the instruction of the Lord… he is like a tree planted by streams of water”. (Psalm 1:2-3)
Today we have heard our Lord give a parable of the kingdom of God being like a tree – the mustard tree, specifically. It begins as a tiny seed, which grows into the biggest of trees.
This is what it is like to have the kingdom grow within us. And it is a wonderful encouragement to those of us who are a bit too honest about ourselves.
We can find it very easy, I think, to bring ourselves down. We know ourselves better than anyone else, and we see our warts and failings the best. But the way Jesus describes the kingdom teaches us that that is not where we remain.
There is a theological term called “progressive sanctification”. It describes the fact that the believer grows in holiness over the course of time. Just like the tiny seed growing into the enormous tree, so too our holiness begins with the hearing of the Gospel message, and grows over time into a well-formed Christian.
We do not need to sit on our laurels and wait for God to grow us into holiness either. This is a process in which we are involved with God. Consider the ancient practise of morning and evening prayer. Christians in generations past have found that spending a bit of time at the start and end of every day with the Lord in prayer builds their relationship up over time.
Sanctification and holiness is not a one-and-done. It is a life of steady, faithful prayer and living that grows up into the biggest tree. Let us not be discouraged by whatever the most recent spiritual failing we find oursevles in is. Rather, look “big picture” – are you different now than you were last year? Ten years ago? To when you were a child? The proof is in the pudding, and your efforts at getting closer to God are bearing fruit. Press on, water that tree, keep spending time with the Lord. One day we will be like he is, and see him as he is. Keep watering that tree.