First reading (Habakkuk 1:2-3; 2:2-4). The prophet Habakkuk (writing 612BC) complains to God about the prevalence of injustice, and God responds by promising to save those who trust in him.
Second reading (2 Timothy 1:6-8, 13-14). Paul encourages Timothy to be faithful to his ministry and to witnessing to Christ.
Gospel (Luke 17:5-10). A little faith, provided it is authentic, can do great things. The disciples are urged to serve God without any claim on a reward.

All three readings speak of faith. The First Reading is part of a dialogue between God and the prophet. Like others before him, Habakkuk is feeling the burden of office.
He complains about the prevalence of injustice and God’s failure to intervene. Then comes the divine response: in due time God will intervene to save those who trust in him. Meanwhile, the upright must remain steadfast in faith.

This brings us to the Gospel, where Jesus says that a grain of authentic faith can achieve great things. The saying about the uprooting of a tree is not to be taken in a literal sense. It is an eastern mode of expression, which means that with faith what looks impossible can become possible.

The parable of the unprofitable servant (‘slave’) would have shocked Jesus’ hearers. A slave had no claim to either wages or thanks from his master, irrespective of how well he might have served him. At the time of Jesus, Judaism was dominated by the notion of merit – God ‘owed’ salvation to humans in return for keeping the Law. Jesus rejects this, and emphasises God’s sheer goodness. The disciples must humbly acknowledge that they are only servants.