Having come down in a cloud, the LORD stood with Moses there and proclaimed his name, "LORD." Thus the LORD passed before him and cried out, "The LORD, the LORD, a merciful and gracious God, slow to anger and rich in kindness and fidelity." (Ex 34:5-6)
It’s always fun to see the passages of Scripture that the lectionary-makers stitch together for us on the major feast days. The passage from Exodus takes us through the second-giving of the LAW on Mount Sinai. But what is most interesting is not the LAW, but the self-revelation that God makes: “a merciful and gracious God, slow to anger and rich in kindness and fidelity." And good old Saint Paul adds a blessing for us in proper Trinitarian form:
The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with all of you. (2 Cor 13:13)
Some folks think that the triple Sanctus (Holy, Holy, Holy) is a reference to the Trinity. Unfortunately, it’s not. Hebrew lacked the superlative. So the only way to express “holiest” is to repeat “holy” three times. And so in the vision of Isaiah, the Seraphim praise God singing:
“Holy, holy, holy is the Lord of hosts!
All the earth is filled with his glory!”