Fasting as a spiritual discipline can be found throughout the Scriptures, ‘though more in the Old Testament. In this passage it is linked with prayer and almsgiving quite naturally. Jesus says “when” rather than “if”, and contrasts the Pharisees, who did everything for human approval (and consequently only received human respect) from what we should do. God sees in secret: including the secrets of our hearts. Looking up to Him for blessing and grace, is the “righteousness” which pleases God.