Then Jesus said to them: "Do you still not understand?" (Mark 8v21)

Are you a great hero or heroine of the Christian faith? Or do you tend to find it a somewhat up and down journey?

I've always rather admired people whose spiritual journey seems to be much more dynamic than my own. I had a friend from college who wrote a blog while facing terminal cancer, and her journey of faith was both humbling and awe-inspiring.

But not all of us are like that! So it was reassuring, when I was speaking to an older and wiser Christian this week, to discover that during a time of serious trial some years ago he had found himself (somewhat unsettlingly) really scared. His openness somehow gave me permission to feel more human about my own struggles.

When we read the Gospels, too, we see that Jesus' first disciples are often rather fragile in their faith journey. Jesus' words to them in Mark 8v21 portray something of their far-from-victorious Christian living: "Do you not yet understand?" he asks them. And in the preceding verses he has expressed similar sentiments: "Do you still not perceive or understand? Are your hearts hardened? Do you have eyes and fail to see? Do you have ears and fail to hear? And do you not remember?" To adapt a famous phrase of Homer Simpson, at this point they seem be more "doh!-sciples" than disciples!

The context, of course, is vital. Jesus has just performed a miracle in which 4,000 people (v9) have been fed with seven loaves and a few fish. It's an event which mirrors an earlier, similar act in which five loaves and two fish feed an even bigger crowd (Mark 6v30-44). The difference is that the first crowd was Jewish, the second very probably Gentile. The inference is clear: Jesus is the living bread for both groups – in other words, for everyone, regardless of ethnicity. What amazing acts!

So here are the disciples who have witnessed two spectacular and similar miracles involving loaves. Moreover, in between them, Jesus has calmed a storm and healed some sick people. Yet, as they embark on a journey by boat (v13), they still begin to worry that they haven't got enough bread with them, and mistakenly think Jesus is having a go at them for their inadequate meal planning (v14-16).

There are two repsonses to this:

It's encouraging that the disciples are sometimes as spiritually slow as we are. As one writer summarises it: "They are worried about having no bread, when they have just witnessed the King of glory multiplying loaves for thousands!" And yet isn't that often so much like our own experience? We look back on the faithfulness of God in the past – perhaps in both dramatic and small, intimate ways – and yet when the next difficulty or trial comes along we immediately start to worry or panic! It's reassuring to know that Jesus' first disciples had similar struggles.

It's challenging that we so easily fail to get the point. Our similarity with the disciples should not make us complacent, however. Yes, it's easy to doubt Jesus even quite soon after he has shown great faithfulness to us in some way. But does he sigh (v12) about us and speak those same words: "Do you still not understand?" He is the utterly reliable Christ who can certainly perform mighty acts but ultimately accomplishes his greatest work through the brokenness of a cross – as he may through the brokenness of our lives. Either way, we can trust him.

Be still my heart, a hymn by John Newton, helps us to ask for God's help when we find ourselves, however often, being more like "doh!-sciples" than trusting disciples of Jesus: "Brought safely by His hand thus far, why will you now give place to fear? How can you lack if He provides, or lose the way with such a Guide? Though rough and thorny be the road, it leads you on, apace to God; then count your present trials small, for God will make amends for all." Amen!

The Rough Guide to Discipleship is a fortnightly devotional series. David Baker is a former daily newspaper journalist now working as an Anglican minister in Sussex.