Isaiah 56:6-7

6“Also the sons of the foreigner Who join themselves to the Lord, to serve Him, And to love the name of the Lord, to be His servants— Everyone who keeps from defiling the Sabbath, And holds fast My covenant—

7Even them 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 nations.”