Bob started by showing a new (plastic) £5 note and pointing out that it says 'I promise to pay the bearer a sum of five pounds' and then talked about God's promises in Hebrews:

Jesus is our anchor.
There is a danger of drifting away, so we need a secure anchor. Our anchor is secured in God's very presence so is therefore secure.
We need to be trusting and patient, holding on firmly to God's promises.