For I hear witness to him that he hath much labour ( πὸνον for ζῆλον, Revised Text) for you (Colossians 1:29; Colossians 2:1; Philippians 2:19-23; 1 Thessalonians 5:12, 1 Thessalonians 5:13; 1 Timothy 5:17; 1 Corinthians 16:15, 1 Corinthians 16:16).
πόνος occurs in the New Testament besides only in Revelation 16:10, Revelation 16:11 and Revelation 21:4, where it means "pain;" in classical Greek it implies "painful, distressful exertion" (comp. κοπιῶ, Colossians 1:29).
It indicates the deep anxiety of Epaphras for this beloved and endangered Church. There is nothing here to point to "outward toil" (Lightfoot), any more than in Colossians 2:1. The apostle loves to commend his fellow labourers (Colossians 1:7; Philippians 2:20-22, Philippians 2:25, Philippians 2:26; 2 Corinthians 8:16-23).
And for those in Laodicea and those in Hierapolis (Colossians 2:15-17; Colossians 2:1). The Church in Hierapolis is added to that of Laodicea, singled out in Colossians 2:1 as a special object of the apostle's concern (on these cities, see Introduction, § 1).
Whether Epaphras were the official head of these Churches or not, he could not but be deeply concerned in their welfare. Colossians 2:17 indicates the existence of a personal link between the Churches of Colossus and of Laodicea.