Matthew 11:28: "'Come to me, all who labor and are heavy laden, and I will give you rest.'"
John 6:37: "'All that the Father gives me will come to me, and whoever comes to me I will never cast out.'"
Isaiah 60:20: "Your sun shall no more go down, nor your moon withdraw itself; for the LORD will be your everlasting light, and your days of mourning shall be ended."
Isaiah 40:31: "but they who wait for the LORD shall renew their strength; they shall mount up with wings like eagles; they shall run and not be weary; they shall walk and not faint."
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The text is public domain:
"Come unto Me, ye weary,And I will give you rest."O blessed voice of Jesus,Which comes to hearts oppressed!It tells of benediction,Of pardon, grace, and peace,Of joy that hath no ending,Of love that cannot cease."Come unto Me, ye wand'rers,And I will give you light."O loving voice of Jesus,Which comes to cheer the night!Our hearts were filled with sadness,And we had lost our way;But Thou hast brought us gladnessAnd songs at break of day."Come unto Me, ye fainting,And I will give you life."O cheering voice of Jesus,Which comes to aid our strife!The foe is stern and eager,The fight is fierce and long;But Thou hast made us mightyAnd stronger than the strong."And whosoever cometh,I will not cast him out."O patient love of Jesus,Which drives away our doubt,Which, though we be unworthyOf love so great and free,Invites us very sinnersTo come, dear Lord, to Thee!
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Each verse of the hymn is drawn from one of the cited passages. The first verse comes from Matthew 11:28; the second verse comes from Isaiah 60:20; the third verse comes from Isaiah 40:31; and the fourth verse comes from John 6:32.
The second half of the second verse (particularly the lines "But Thou hast brought us gladness / And songs at break of day") also seems to be drawn from part of Psalm 30:5: "Weeping may tarry for the night, but joy comes with the morning."