Isaiah 56:6-7 (New International Version)

 ⁶ And foreigners who bind themselves to the LORD
       to serve him,
       to love the name of the LORD,
       and to worship him,
       all who keep the Sabbath without desecrating it
       and who hold fast to my covenant-

 ⁷ these I will bring to my holy mountain
       and give them joy in my house of prayer.
       Their burnt offerings and sacrifices
       will be accepted on my altar;
       for my house will be called
       a house of prayer for all nations."