Haydock Catholic Bible Commentary
If there be, therefore, any consolation. If you have any desire to comfort me in Christ, or for Christ's sake. (Witham)
Esteem others better than themselves. St. Thomas Aquinas (22. q. 162. a. 3.) puts the question, how an innocent man can with truth think himself worse than the most wicked of men? He answers, that a man who has received very extraordinary gifts from God, cannot think these gifts less than what any other has received; but he may reflect that he has nothing, and is nothing of himself. And a man truly humble considers only his own sins and failings, and is persuaded that any other person would have made better use of the same graces; which agrees with what follows, (ver. 4) not considering the things that are his own. (Witham)
The things that are his. Self-love and self-interest are the two great sources of divisions. The Christian religion teaches a contrary doctrine. (Calmet)
Who being in the form  of God, (that is truly, properly, and essentially God from eternity, as the ancient Fathers here observed against the Arians) taking the form of a servant, (i.e. taking upon him our human nature) became truly a man, and as man the servant of God, but remaining always God as before, thought it not robbery, no injury to his eternal Father, to be equal, to be esteemed, and to declare himself equal to God, to be one thing with him: as on divers occasions he taught the people, as we have observed in the notes on St. John's gospel, &c. (Witham)
In forma Dei, Greek: en morphe Theou. See St. John Chrysostom (tom. iv. p. 31. 32. Greek: log. 5.) where he shews how many heresies are confuted by these words: and says, Greek: e morphe tou doulou, e phusis doulou....kai e morphe tou Theou, Theou phusis. See St. Gregory of Nyssa...3. cont. Eunom.; St. Augustine, lib. 1. de Trin. chap. 1. &c.
But debased himself: divested himself of all the marks of greatness, for the love of mankind. The Greek text signifies, he made himself void; on which account Dr. Wells, instead of made himself of no reputation, as in the Protestant translation, has changed it into emptied himself; not but that the true Son of God must always remain truly God, as well as by his incarnation truly man, but that in him as man appeared no marks of his divine power and greatness. --- Made to the likeness  of men, not only as to an exterior likeness and appearance, but at the same time truly man by uniting his divine person to the nature of man. --- In shape  (or habit) found as a man: not clothed exteriorly only, as a man is clothed with a garment or coat, but found both as to shape and nature a man; and, as St. John Chrysostom says, with the appearance of a sinful man, if we consider him persecuted by the Jews, and nailed to an infamous cross. (Witham)
Exinanivit Semetipsum, Greek: ekenose, evacuavit, a kenos, vacuus. See St. John Chrysostom, hom. vii.
In similitudinem hominum factus, Greek: en omoiomati. St. John Chrysostom, p. 40. Greek: log. x. See Romans viii. in similitudinem carnis peccati.
Et habitu inventus ut homo, Greek: schemati euretheis os anthropos. St. John Chrysostom, ibid. i.e. habitu factus est.
God....hath given him a name, &c. The name or word Jesus represents the dignity of him who is signified by the name, and who is exalted even as man, above all creatures in heaven, earth, and hell; all which creatures either piously reverence him, or are made subject to him against their will, that every tongue may confess our Lord Jesus to be now, and to have been always, in the glory of his Father, equal to him in substance and in all perfections. (Witham)
Php 2:10 we shew respect when the name of our sovereign is mentioned, may we not express our respect also at the name of Jesus; and if to his name, why not to his cross as well as to the throne of the king?
With fear and trembling. That is, be equally upon your guard against presumption and despair. St. Paul is anxious to inspire a just confidence in Jesus Christ, but he is not less solicitous to root out all self-confidence arising from our supposed merits or excellence.
It is God who worketh in you both to will and to accomplish. We can neither have a will, nor begin, nor fulfil any thing of ourselves, in order to a reward in heaven. (Witham) --- Our free-will is not taken away, or we should not be commanded to work; but it is added, with fear and trembling, says St. Augustine, that we might not be proud of our good works. (De grat. et de lib. ab. chap. ix.)
To my glory, &c. That is, I beseech you to continue in faith, and comply with the word and doctrine of the gospel, that I may have glory, and rejoice together with you in the day of Christ, when he shall come to judgment. (Witham)
and if I be made a victim upon the sacrifice  and service of your faith, I rejoice, &c. The sense of these obscure words seems to be: that I shall rejoice, and you also may rejoice and congratulate with me, if after having first offered up you faith and obedience to the gospel, as an acceptable sacrifice to God, I myself (or my blood, by martyrdom) be also added, and poured out as a second sacrifice upon the other. It is be understood with an allusion to those sacrifices of the old law called libations, consisting of liquid things, as wine, oil, blood, which were poured out, or at least sprinkled, upon other victims and things sacrificed: so that he compares the shedding of his blood to these libations, and their submission to the faith of Christ to the sacrifice before offered to God. (Witham)
Sed etsi immolor super sacrificium, et obsequium fidei vestræ, Greek: alla ei kai spendoma: epi to thusia, kai leitourgia tes pisteos umon: spendesthai, est libari, eo modo quo sanguis effunditur super sacrificia.
To send Timothy. It appears that St. Paul could not send Timothy to Philippi till some time after his deliverance from prison, about the year 63 of Jesus Christ [the year A.D. 63]. (Tillemont) --- In the succeeding verse, we see the high esteem in which Timothy was held by this apostle.
All seek the things that are their own; i.e. many do so. (Witham)
That I also. This did not take place till full two years were expired, in the year 64: (Tillemont) and others are of opinion, that he was in Macedon when he wrote his first epistle to Timothy. (Theo. Atha. Tille.)
Epaphroditus....your apostle, and the minister of my wants. Epaphroditus had also laboured after St. Paul, and is thought to have been the bishop of the Philippians; thus he might be called their apostle; though, as others conjecture, the word apostle may be here applied to him as one sent by the Philippians to St. Paul with contributions to supply his wants. (Witham)
And I may be without sorrow; without the great concern and trouble that I am now in for you. (Witham)
Delivering up his life to persecutions, and to this danger that he was in by a sickness which was mortal, had not God restored him his health. He came with your charities, to supply that which was wanting on your part, or which I stood in need of; and I am persuaded you desired to do it sooner, if you had met with an opportunity. (Witham)