Being filled with the fruits of righteousness - That which righteousness in the heart produces. The fruits, or results, will be seen in the life; and those fruits are - honesty, truth, charity, kindness, meekness, goodness. The wish of the apostle is, that they might show abundantly by their lives that they were truly righteous. He does not refer to liberality merely, but to everything which true piety in the heart is fitted to produce in the life.
Which are by Jesus Christ -
(1) Which his religion is fitted to produce.
(2) Which result from endeavoring to follow his example.
(3) Which are produced by his agency on the heart.
Unto the glory and praise of God - His honor is never more promoted than by the eminent holiness of his friends; see the notes at John 15:8. If we wish, therefore, to honor God, it should not be merely with the lips, or by acts of prayer and praise; it should be by a life devoted to him. It is easy to render the service of the lips; it is far more difficult to render that service which consists in a life of patient and consistent piety; and in proportion to the difficulty of it, is its value in his sight.