Charles H. Spurgeon on Psalms 103:8

Plenteous in mercy. It is a thing marvellously satisfactory and pleasing to the heart of a man to be still taking from a great heap; and upon this ground are those proverbial sayings, There is no fishing like to fishing in the sea, no service like the service of a king: because in one there is the greatest plenty and abundance of that kind of pleasure that fishers look after; and for them that serve, and must live by their service, there is none like that of princes, because they have abundance of reward and of opportunity whereby to recompense the services of those that do wait and attend upon them... And upon the same ground it is that the Scriptures, in several places do not only assert and testify that God is "merciful" and "gracious, "but abundant in mercy and full of grace; and not simply that there is redemption in him, but plenteousness of redemption, Ps 86:5 130:7; Isa 55:7, "Let the wicked forsake his way, "etc.; "Let him return unto the Lord and he will have mercy upon him; and to our God, for he will abundantly pardon." The commodity which we stand in need of is mercy and the pardon of our sins, because we have been unholy and ungodly creatures; this commodity is abundantly in God. There it is treasured up as waters are in the store-house of the sea; there is no end of the treasures of his grace, mercy, pardon, and compassion. There is no man, being in want, but had rather go to a rich man's door to be relieved, than to the door of a poor man, if he kuoweth the rich man to be as liberal and as bountifully disposed as the poor man can be. John Goodwin, on, "Being filled with the Spirit."