When that day comes (literally “on that day”) is used three times in John’s Gospel (here and in 16.23,26). Although in traditional biblical language the term refers to “the last day,” the day of God’s final intervention, in the present verse it refers to verse 18. Verses 18 and 20 both refer primarily to the time of Jesus’ resurrection, but the thought is obviously extended to the permanent presence of the risen Lord with his people everywhere.

It is essential that the time referred to by that day be understood as the time when the disciples would see Jesus again (verse 19) or when Jesus would live again (implied in verse 19). In some languages an equivalent of When that day comes may be “When that happens.” It may be made even more specific in some languages as “when I come back to life.”

Once again the pronouns you and I are emphatic.

I am in my Father is almost identical with I am in the Father (10.38). Note also 14.10-11 and 17.21-23. Die Bibel im heutigen Deutsch expresses this idea of oneness as “I am inseparably one with the Father. Even so shall you be one with me and I with you.” Here, as in the other passages listed, it may be difficult to express the idea of one person being in another person. It may be best expressed as “lives in” or “is united with” or even “is one with.” As in many similar contexts, expressions involving one person being in another may be expressed as “just like one”; for example, “I and my Father are just like one person, and you and I are just like one person.”

Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on the Gospel of John. (UBS Handbook Series). New York: UBS, 1980. For this and other handbooks for translators see here .