Romans 16:4

who for my life laid down their own necks; unto whom not only. give thanks, but also all the churches of the Gentiles:

'laid down their own necks' -Paul had encountered danger in both Corinth and Ephesus. (See Acts 18:12; Acts 19:23). 'Risked their own necks' (NASV), 'who once risked their very necks for my life.' (Wms) 'Laid down is, literally, placed under (the ax).' (Vincent p. 178)

'but also all the churches of the Gentiles' -'had reason to be thankful to them, for having rescued the Apostle of the Gentiles from danger.' (Alford p. 970) 'The language implies that the incident referred to had occurred long enough ago for all the Gentile Churches to be aware of it..' (Gr. Ex. N.T. p. 718)

'They laid their necks on the line for Paul. It's interesting that being in Christ results in so much service; everybody "works". They all accepted grace and worked as though there were none. Anyone who says teaching justification by grace results in indolence hasn't paid attention to the fruit of grace (see 1 Corinthians 15:10 and Romans 16:3; Romans 16:5; Romans 16:12)' (McGuiggan p. 440)