Mark 4:26 – 29: The kingdom of God is as if a man should scatter seed on the ground. He sleeps and rises night and day, and the seed sprouts and grows; The earth produces, first the blade, then the ear, then the full grain in the ear.
Mark 4:30 – 32: What can we compare the kingdom of God, it is like a grain of mustard seed, which, when sown in the ground, is the smallest of all the seeds, yet when it is sown it grows up and becomes larger than all the garden plants and puts out large branches, so that the birds of the air can make nests in its shade.
Jesus never promoted the idea that we had to have great faith to be accomplished and faithful Christians. Jesus encouraged His followers to have faith but did not promote a faith beyond simple belief. When the disciples asked Jesus to increase their faith, He quickly adjusted their thinking, bringing to light that small and simple mustard seed faith was enough to be and do whatever is needed.
The mustard seed is usually between 1 and 2 millimeters in diameter. It is very small. But when mixed with outside influences, it becomes much more: when ground up and mixed the with water, vinegar and other liquids the mustard seed produces the yellow condiment known as prepared mustard. Making further use of this Biblical metaphor, our faith is primarily cultivated by a mixture of life experience, the Word of God, the Holy Spirit and encouragement from others with a sensible and Biblical faith view. The whole process takes time and perseverance, but the end of it is a simple faith that hurdles challenges and seizes opportunities.
Unfortunately, I have seen sincere and passionate Christians experience a fair amount of confusion and desperation, seeking after a kind of great faith, not the small and simple faith that Jesus encouraged. When I was a teenager, I remember wanting to have more faith so I could be a better person and accomplish more in my life. There was a very alluring movement that was just getting started in the church at the time, advocating a kind of blessing-on-demand approach to faith: this authoritative approach encourages us to take authority over our wants and needs by declaration.
I suppose there is some degree of faith hidden in this authoritative approach somewhere, but to me it does not seem to encourage the cultivation of a simple, non-assuming, and enduring mustard seed faith that is developed over time. Being a faithful member of a good church where sensible people of faith share their experiences, where the Word of God is still the centerpiece of worship and the Holy Spirit can be felt and heard through spiritual impression is where simple faith is cultivated.