2 Thessalonians 2:14: "To this he called you through our gospel, so that you may obtain the glory of our Lord Jesus Christ."
Matthew 28:18-20: "18 And Jesus came and said to them, 'All authority in heaven and on earth has been given to me, 19 Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, 20 teaching them to observe all that I have commanded you. And behold, I am with you always, to the end of the age.'"
Mark 16:15-16: "15 And he said to them, 'Go into all the world and proclaim the gospel to the whole creation. 16 Whoever believes and is baptized will be saved, but whoever does not believe will be condemned.'"
1 Corinthians 15:58: "Therefore, my beloved brothers, be steadfast, immovable, always abounding in the work of the Lord, knowing that in the Lord your labor is not in vain."
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2 Thessalonians 2:14 is referred to in the title line (in the refrain): "Listen, listen, God is calling."
Matthew 28:18-20 (but mostly just verse 19) is paraphrased in the hymn's second verse: "Let none be forgotten / Throughout the world. / In the triune name of God / Go and baptize."
Mark 16:15-16 is referred to in the first verse: "Jesus gave His mandate: / Share the good news."
1 Corinthians 15:58 seems to appear in the first half of the third verse ("Help us to be faithful, / Standing steadfast"), but the hymn text also bears some similarity to Colossians 1:23: "if indeed you continue in the faith, stable and steadfast, not shifting from the hope of the gospel that you heard, which has been proclaimed in all creation under heaven, and of which I, Paul, became a minister."
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The alliteration in "standing steadfast" provides a sense of constancy, which matches the meaning of the phrase.
