Colossians 4:11

And Jesus, which is called Justus
The former of these names is the same with Joshua, and was very frequent with the Jews, and the later a surname that was sometimes given to men remarkable for holiness and righteousness: so Joseph, called Barsabas, is surnamed Justus, ( Acts 1:23 ) and James, the brother of our Lord, was called by the Jews James the Just ^F13: whether this man was not the same with Justus of Corinth, whose house joined to the synagogue, and into which Paul entered, ( Acts 18:7 ) is not certain, but is likely: who are of the circumcision; were Jews, were circumcised persons, though not now sticklers for circumcision, and the rest of the ceremonies, as appears by what follows: this is to be understood of all the above persons, that sent their salutations to this church; though some confine it to Marcus, Barnabas's sister's son, and to Jesus, called Justus:

these only are my fellow workers unto the kingdom of God;
who assisted him in preaching the Gospel of the kingdom of God, and in promoting the honour and interest of Christ. These were the only persons of the Jewish nation that were then at Rome under that character; from whence it appears that Peter was not there at that time: the apostle adds,

which have been a comfort unto me;
under his afflictions and sufferings, by visiting him, conferring with him, praying for him, communicating to him, and labouring in the Gospel in his room and stead.