"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, every one who keeps the sabbath, and does not profane it, and holds fast my covenant--
Revised Standard Version of the Bible, copyright 1952 [2nd edition, 1971] by the Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.
(Revised Standard Version - Holy Bible)