Psalm 67:1-2 (ESV)
May God be gracious to us and bless us
and make his face to shine upon us, Selah
 that your way may be known on earth,
your saving power among all nations.
Why should God be gracious to you? We know it is not because we deserve it. If God gives us what we deserve it would be just, but it would not be gracious. It would be earned. Grace gives what is undeserved. There are several reasons why God is gracious: His love for His children, His nature to be so, His faithfulness to His promises … . But in the opening verses of this Psalm the reason why God is gracious to us is so that His ways may be known throughout the earth.
If God is gracious to His children how will the world find out? They will tell the world how gracious God has been. They will live in such gratitude for what God has done for them that people will ask them what makes them tick. They will live so other-worldly that they will stand out in the crowd. We are created for the praise of God’s glory. Because of our sin we do not give God glory, so He saves us from our sin and enables us to live for just that reason. This means growing in our knowledge of God and the grace that He has so lavishly poured out on us.
God wants the world to know just what a great God He is, not because He is on some cosmic power trip, but because He is the greatest thing in all the universe. The One who made the universe is greater than all the wonders He has made. This is an astounding thought, for the created order contains a vast numberless host of wonders to see and hear and taste and feel. Mankind has barely begun to plumb the depths of the wonders of the created order. The world and beyond is a testimony to the greatness of our God.
He showers grace on us and brings us into a living relationship with Himself so that we can tell the world just how great and gracious and marvelous He is. He is gracious to us so that the world can behold the wonders of grace. He is gracious to us so that others will hear of His greatness and come to believe in Him as well. The very fact that you are saved is a call upon you to be an evangelist. God is the lone Creator of all that is and His desire is that all He has created know of His greatness.
This is a striking thing for the Israelite David to write. What vision did David have of world evangelism? What did he know about people from every tribe and people and tongue gathering around the throne of God to unite in praise together to the glory of God? Yet here he is writing about all the nations hearing about God’s grace. The Gospel has never been for Israel only. Israel was never meant to be the only nation brought into covenant relationship with God. The Gospel is for everyone. That truth is in the Old Testament. Paul refers to it as the mystery of the Gospel. Whatever Old Covenant saints knew of the universal offer of life, it became abundantly clear after Christ left.
The Great Commission is a fulfilment of the Gospel that is introduced in the Old Testament. What a glory the Gospel is. What a plan God has concocted and brought into being. What a day is coming when this age shall end and the new age of all nations worshipping the triune God in sinless praise!!