Because holding onto things has strong resonances in the Christian tradition.
I'm no fan of John Lennon's Imagine: 'Imagine there's no heaven, above us only sky...imagine there's no countries...nothing to kill or die for...no religion too'.
No justice or passion? People floating around in white drapes saying 'peace' when there is no peace? No thanks.
In contrast, Christians are encouraged to 'Hold fast to what is good' (Thessalonians) and to hold on tenaciously when things are tough. But holding on can also be negative. Holding onto people who need to be let go of; holding onto memories which need healing; holding grudges. Perhaps it's a question of what to hold tightly and what to hold lightly.
Holding on tightly or lightly is a conundrum for the selection process in the Church of England, but also for anyone who's ever needed a bit of divine guidance (you know, that nudging, that prompting, that hunch).
Here's the conundrum: You think God might be calling you to do something. You approach your parish priest and they listen to you stumbling through a badly articulated explanation of a feeling, that might be a hunch, that might be a 'calling', say to Ordination, then they tell you to go away 'and when you're sure, come back and see me.'
But when will you be sure? Months, even years down the line, when you have started to articulate this feeling/hunch/nudge a bit more fully, they send you off to a BAP (Bishops' Advisory Panel) where for three days you are watched, assessed and 'interviewed' by various CofE 'experts', lay and ordained, to see if they too can 'discern' a calling from God.

On one level you must hold onto this sense of calling very lightly because if you don't, you're in for a tremendous disappointment when that 'sorry, it's a no' phone call comes through. Ideally you want to respond with a happy shrug and the words 'ah, no worries, I'll go back to teaching. Thanks. Byeeeee'. At the same time, how can you not hold tightly onto something that's so potentially life changing if, as it turns out, you had the right, as opposed to the wrong, end of the stick.
I had to go and see the Principal in my second year of Theological College. Turns out I was right about the original calling but I'd had a further hunch about my vocation and now wished to slant my training towards 'Pioneer Ministry', which was the new sexy at the time. By now I knew the kind of words to use: 'I've had time to reflect....just want to be obedient...'
The Principal had the nicest study in Christendom. The Principal was wise. The Principal was a good listener. He listened to my articulating how I felt drawn to be a Pioneer Minister. He said of my conviction: 'I think you have the right combination: you're holding it firmly but lightly.' So far so good. It wasn't in his gift, I knew that; but he would support my application. I continued to hold onto it firmly but lightly. Actually I didn't manage the lightly bit very well. At the end of the month my application was turned down. I was really upset.
And in ministry day to day I still struggle to hold some
things, some people, lightly. I don't have a problem with the tightly bit - I have a good memory for faces and names and can hold situations in prayer for years. It's the lightly bit. But when people get ill, when they die; when they move away, disagree, can't be bothered or are too tired, make mistakes and let you down; when our plans seem such a good idea and our programmes so very important to mission that we're thrown into confusion when they don't 'work'; that's when we have to learn to hold on. Lightly.