Thomas Watson, "How God is His People's Great Reward," in Puritan Sermons, 1659-1689, Vol. 3, p. 68:
II. QUESTION. How is God his people's reward?
ANSWER. In bestowing himself upon them. The great blessing of the covenant is, "I am thy God." The Lord told Abraham, kings should come out of his loins, and he would give the land of Canaan to him and his seed; (Gen. xvii. 6; ) but all this did not amount to blessedness. That which made up the portion was, "I will be their God." (Verse 8.) God "will not only see that the saints shall be rewarded, but his own self will be their reward." A king may reward his subjects with gratuities, but he bestows himself upon his queen: God saith to every believer, as he did to Aaron, "I am thy part and thine inheritance;" (Num. xviii. 20; ) and as the king of Israel said to Benhadad, "I am thine, and all that I have." (1 Kings xx. 4.)
Abraham sent away the sons of the concubines with a few gifts; but he settled the inheritance upon Isaac. (Gen. xxv. 5, 6.) God sends away the wicked with riches and honour, but makes over himself to his people. They have not only the gift, but the Giver. And what can be more? As Micah said, "What have I more?" (Judges xviii. 24: ) so what hath God more to give than himself? What greater dowry than Deity? God is not only the saints' rewarder, but their "reward." "The Almighty shall be thy gold:" (Job xxii. 25: ) so much the Hebrew word imports. The sum of all is: the saints' portion lies in God: "The Lord is the portion of mine inheritance and of my cup." (Psalm xvi. 5.)