6 "And the foreigners who join themselves
to the Lord,
to minister to him, to love the name
of the Lord,
and to be his servants,
everyone who keeps the Sabbath
and does not profane it,
and holds fast my covenant -
7 these I will bring to my holy mountain,
and make them joyful in my house of prayer;
their burnt offerings and their sacrifices
will be accepted on my altar;
for my house shall be called a house of prayer
for all peoples."
I may write some day a longer version of our motives for adopting, but for the time being, these verses will present one aspect of our motive. The idea of a "foreigner" being united to the people of God through a God-enacted covenant is remarkable. God has intended from the beginning of his creative plan to redeem people from every tribe, tongue, nation, and people group to be a people for his own possession. God has always intended to save the foreigner (i.e. non-Israelites), and bring them to his holy mountain.
With this passage in Isaiah, the focus is on nationality. The foreigner is a non-Israelite. For our adoption, although nationality is going to be quite obvious, our hope is that through the national differences of our family composition, people will see the heart of God for the "foreigner," i.e. the one who is not part of the covenantal family of God. We don't want people to look at our family and think that we have accomplished some sort of philanthropic task by adopting. We want to be able to tell people that God has adopted us, foreigners to the covenant and spiritual orphans, into his family, and it is the least we can do to display that same affection to a foreigner and orphan. So, one of our motives for adopting boils down to the gospel. God is in the business of adopting, i.e. bringing those who are not family members into an eternal relationship with a loving Father. We want to display that heart in and through our adoption.
Deut. 10:18-19 - He executes justice for the fatherless and the widow, and loves the sojourner, giving him food and clothing. Love the sojourner, therefore, for you were sojourners in the land of Egypt.