But ye know the proof of him
They had had an experiment of him, a trial of his spirit, and a proof of his gifts and ministry, when he was among them with the apostle at his first preaching the Gospel to them, to the conversion of Lydia, and of the jailer, and their households, which laid the foundation of a Gospel church state among them, see ( Acts 16:3 Acts 16:12 ) . The Vulgate Latin version reads in the imperative, "know ye the proof of him"; but the former reading is to be preferred:
that as a son with the father, he hath served with me in the Gospel;
he served not the apostle, but with him; he served God as the apostle did, in the Gospel of his Son; he served Jesus Christ, whose Gospel he preached, the interest and spread of which he greatly laboured in with him, as a fellow servant or work fellow; see ( Romans 16:21 ) ; which expresses the modesty of the apostle, and the great honour put upon Timothy, and which was not abused by him; for as a son honours, obeys, and imitates his father, so did he honour the apostle, and give him all respect and reverence that was due to him on account of his office, age, and usefulness; and obeyed his orders cheerfully, going wherever he sent him, and doing whatever he bid him; and imitated him in his ministry, in his constancy, diligence, and zeal, having a true filial affection for him.