The first verse of Psalm 67 says
God be merciful to us and bless us,
And cause His face to shine upon us, Selah
Though the Psalm is built on the priestly benediction, it is not a copy. There are intentional changes in the text.
For example, the priestly blessing in Numbers begins with "The LORD bless you and keep you" that is "YHWH bless you and keep you." "YHWH" is the personal God of His covenant people. This is how God is addressed in Numbers.
I Psalm 67 however, the verse goes "God be merciful to us and bless us." that is Elohim or the general term for God. This intentional change was made in order to stress to the reader that this is a universal call of the mighty God and this regards His gift of salvation to the whole world, not just the Jews.
The psalmist here is asking God for blessings so that the world may know that He is God and praise and worship Him. Psalm 67 is a missionary hymn!
Verse 2 makes this abundantly clear.
That Your way may be known on earth,
Your salvation among all nations.
The psalmist is asking God for blessings for the the sake of the salvation among all the nations.
Have you ever prayed like that?
Have you ever prayed that God would bless you, your family, your church, your country, so that others may come to know His ways and receive His salvation?
I love finding these beautiful hymns and prayers in the Bible, because they teach me how to pray. The prayers I read in the Bible challenge me and my traditional way of praying. Many times we learn to pray by listening to others pray, and there is nothing wrong with that. But sometimes we can get in a rut, where all our prayers are very similar and repetitive. But when we come across prayers like the one found in this beautiful hymn (Psalm 67) we are challenged to pray differently, or at least to add some variety to our prayer life.
So I would like to encourage you to learn from Psalm 67 and to pray for blessings, not for personal gain, but that others may see the power of God at work in your life, in your family, in your church, and may come to know Him and accept Jesus as their Lord and Savior.