Wake discusses John 15: 1-11 in which Jesus tells his disiples that they need to abide in Him to have a fruitful life. Abiding in Jesus is marked by engaging with the scripture and prayer, since that is how one cultivates a realationship with Jesus.  In order to produce more fruit,  the Father will prune a branch  that abides in Jesus, but the other option is to be cut off.  Joy is one of the main fruit of abiding in Jesus.