So that (or “in order that”) marks the ultimate end of Paul’s staying on with his Philippian friends. Because of the rather complex relation of the clauses, it may be necessary to introduce verse 26 with a separate sentence, for example, “The purpose of all this is that when I am with you again…” or “I will do this so that when I am with you again….”
When I am with you again is literally “by means of my coming to you again.” “Coming” is the very word which Paul uses of the coming of Christ at the day of judgment (1 Cor 15.23; 1 Thes 2.19; 3.13; 4.15; 5.23; 2 Thes 2.1, 8). In this context it refers to Paul’s visiting again with his friends (Knox “when I come once again to visit you”; Phillips “when I come to see you again”).
Since the Greek here is somewhat obscure (literally, “that your pride may abound in Christ Jesus in me”), interpreters differ as to whether Christ or Paul is the object of “pride.” Some translators understand the object to be Christ: “so that in me you may have ample cause to glory in Christ Jesus” (Revised Standard Version); “and so you will have another reason to give praise to Christ Jesus on my account” (Jerusalem Bible); “thus you will have ample cause to glory in Christ Jesus over me” (Moffatt). Others, however, regard the immediate cause of pride as being Paul himself. This is the position taken by Good News Translation: you will have even more reason to be proud of me (New English Bible “your pride in me may be unbounded”; cf. Goodspeed Phillips). If one follows the first interpretation, one may translate “in this way you will have every reason to honor Christ Jesus,” or “… some give praise to Christ Jesus.” If, on the other hand, one follows the second interpretation, the rendering may be “you will have even more reason to be proud because of what I have done.”
In your life in union with Christ Jesus is an attempt to bring out the meaning of a characteristic Pauline expression, “in Christ Jesus” (cf. 1.1). Even a glance at various translations will show how difficult it is to translate this formula adequately. Goodspeed makes it an adjectival expression, “Christian exultation.” Phillips takes it to mean “as your minister in Christ.” Apparently Paul is saying that the Philippian Christians’ pride in him is developed in the sphere of Christ Jesus. The basic meaning is one’s intimate union or fellowship with Christ.
It is not easy to relate clearly the expression in your life in union with Christ Jesus to what precedes. Furthermore, in many languages life must be expressed by a verb. Therefore, the final phrase may be rendered in some languages as “as you live your life joined to Christ Jesus,” or “… as one with Christ Jesus.”
Quoted with permission from Luo, I-Jin. and Nida, Eugene A. A Handbook on Paul’s Letter to the Philippians. (UBS Handbook Series). New York: UBS, 1977. For this and other handbooks for translators see here .