Let Israel hope in the Lord - In such circumstances of affliction and distress, let not the people of God despair. In the darkest night, in calamities deep and prolonged, let not those who love God despair. The morning will dawn; the light will break in the east; deliverance and joy will come. The Hebrew here is, “Trust, O Israel, in the Lord.” The design of the Psalmist seems to be, from his own experience, to persuade others - the afflicted people of God - to put their trust in Him in whom he had himself hoped. From the very depths of affliction, guilt, and almost despair, he had looked to the Lord: encouraged and persuaded by his example, he would now entreat the people of God everywhere and always, in like manner, to trust him.
For with the Lord there is mercy - He is merciful, and in his mercy we may trust.
And with him is plenteous redemption - It is ample; it is full; it abounds. It is not limited; it is not exhausted; it cannot be exhausted. So we may always feel when we come before God, that his mercy is ample for all the needs of all the sinful and the suffering; that the provisions of his grace are unexhausted and inexhaustible. Applying this, as we may, to the work of the Saviour, we may feel that the redemption which is in him is adequate to the needs of a world, and that although numberless million have been saved by it, yet that it is still as rich, as full, and as free as it was in the beginning; as the ocean, though from the beginning of the world it has supplied the materials for rain and dew to water the hills, the vales, the continents, and the islands, is still full; as the light of the sun, though for thousands of ages it has poured its light on the planets, and on all the vast space between itself and those orbs, and has sent out its light into the vast regions beyond, still shines with undiminished splendor, and pours its floods of day and of glory on all those worlds.