Romans 16:13

Ῥοῦφον τὸν ἐκλεκτὸν ἐν Κυρίῳ : for the name see Mark 15:21. If Mark wrote his gospel at Rome, as there is ground to believe, this may be the person to whom he refers. In the gospel he is assumed to be well known, and here he is described as “that choice Christian”. ἐκλεκτὸν cannot refer simply to the fact of his election to be a Christian, since in whatever sense this is true, it is true of all Christians alike; whereas here it evidently expresses some distinction of Rufus. He was a noble specimen of a Christian. καὶ τὴν μητέρα αὐτοῦ κ. ἐμοῦ : where she had “mothered” Paul we do not know. For the idea cf. Mark 10:30.