The two days are those which according to 4:40 he spent with the Samaritans. The verse also connects with 4:3.
All three Synoptic Gospels also record this proverb (Mt 13:57; Mk 6:4; Luke 4:24) in reference to his own home town Nazareth, but here it seems to refer to Judea and particularly to Jerusalem where Jesus performed so many signs in their presence“ and yet they did not believe (John 12:37). Jerusalem was the headquarters of ”his own people“ who ”did not receive him" (John 1:11; 5:43).
If Jerusalem rejected him, Galilee welcomed him. His fame had reached there before he himself did, carried by Galileans who had been in Jerusalem for the passover of John 2:13ff, and had seen “the signs which he did” (2:23). It was not until a year later that his Galilean following began to dwindle (6:66).
Here, we realise that how motives can affect final outcome. Galileans received him because of the signs they saw, not because who he truly was (4:42). Thus, “their very acceptance of him was in its own way a rejection”.
Another point worth mentioning. The word translated as “welcome” (ἐδέξαντο - δέχομαι) is different from another word that means “acceptance/ receive” used in John 1:12; 5:43 - (λαμβάνω).
Jesus is back to that place where he first manifested his glory and the disciples believe in him there (John 2:1–11). On that occasion, we could say old life was transformed into new life, this time life will be snatched back from the brink of death.
The “royal official” indicates that this man was probably an official of Herod Antipas, tetrarch of Galilee (4 BC - 39 AD) who was popularly called “king” (cf. Mk 6:14), although the Roman Emperor withheld the full royal title from him. Some have suggested an identification with Chuza, Herod’s steward (Lk 8:3).
Whether he was a Jew or a Gentile it is debatable. Some say that there is nothing to suggest that this man was a Gentile, as was the centurion of Mt 8:5–13 and Luke 7:2–10, whose ‘servant’ (Matthew) or ‘slave’ (Luke) was cured on one occasion when Jesus was in Capernaum.
But some commentators point to the fact that in John 3, Jesus offers new life to a Jew, in John 4:1–42 to the Samaritans, and here to a gentile. Thus, in a unique way John would present an expansion of Jesus’ mission (cf. Acts 1:8).
The ‘royal official’ is not just an official, he is also a father. The trip from Capernaum to Cana was approximately 40 km by road which climbs around 410 meters.
The situation of the son had to be serious because the father “was begging” Jesus. Some translate the end of this verse as “he was at the death’s door”.
Jesus tells his disciple “come and see” (1:39), the father begs Jesus “come and heal”.
Jesus’ recent experience in Jerusalem was fresh in his mind. Many had accorded him a superficial belief there when they saw his signs without grasping their deeper meaning (John 2:23).
Although Jesus responds to the royal official, his statement is in plural “you”. Jesus is criticising the superficial attitude that only wants to see the signs and wonders. There is a double negative used in Greek “you will (1) not (2) not believe” translated as “never”.
At the end of the Gospel Jesus will proclaim blessed those who did not see and yet believe (John 20:29).
The father seems to ignore Jesus’ criticism about the nature or quality of faith. He knew what he wanted and he was sure that Jesus was the only one who could do it. So he politely insists (the aorist imperative - “come down”) for Jesus to come and heal his son. It is normally used when an inferior addresses a superior, denoted by the vocative “Lord”.
He is a royal official, so he knows how to speak to the authority, but in this case he speaks as the father pleading for the life of his child - notice the shift from “my son” to “my child” an expression of affection. Thus, the imperative functions like prayer request. We have the same thing in “our Father” (Mt 6:9–13 - also aorist imperatives are used there).
Unlike the centurion from the Synoptic record, this royal official does not ask Jesus to say a word and work the cure from a distance, but that is actually what happened: “Go, your son lives”. The first verb is an imperative and the second in present indicative. Some translations put it “your son will live”, pointing that the present indicative in this case contains within it a future sense.
The verb “to live” serves as a perfect counter to previously imminent death, yet it also touches upon the important theme of “life” presented by the Gospel which is always available (cf. 20:31).
Jesus, the true king, commanded this royal official and he obeyed. Moreover, the narrator states that the man believed the word that Jesus spoke. The Word spoke the word and the man believed - there was no sign yet.
With nothing but the word of Jesus the royal official begins the descent from Cana to Capernaum. Before he could even reach his home, his servants met him along the way and reported that his son was alive using the exact word Jesus used: lives “ζῇ”.
It seems that the servant diligently attended to the sick child and could say exactly at which hour he got better. The cure had taken place suddenly, yesterday, at the seventh hour - 1 pm.
We do not know what the father was doing from 1pm yesterday, when he heard Jesus’ words and left. But, it is interesting to notice that he did not go home immediately. Apparently, he spent some time in Cana or around doing some sort of business. Did the words of Jesus take away all the concern about the health of his child?
Notice the movement in this section of the Gospel from a “royal official” (4:46), to “the man” (4:50), to “the father” (4:53). That statement prepares us for what is going to happen
“Yesterday”, the royal official believed Jesus’ words. Then, as the father he believes in Jesus with his entire household (wife, children, slaves and other dependents).
St. Cyril of Alexandria commenting on this passage of the Gospel says that Jesus’ word healed two people: the son (his disease) and the father (his weak faith).
We could add that Jesus’ word healed his entire household.
Interestingly, both signs are connected with Cana and both took place after Jesus’ arrival from Judea. The first sign in Cana after Jesus returned from Judea after being declared by John the Baptist the Lamb of God (cf. 1:28–29 and 2:11); the second sign took place after he came from the Passover in Jerusalem narrated in John 2:13ff; 4:3; 4:43.
Apparently, the signs performed in Jerusalem (John 2:23) do not come into the reckoning here. The Evangelist at this point indicates only the two signs that took place in Galilee.