Which persons of the Trinity are attached to which noun in John 1:18 No one has ever seen God[1]; the only God[2], who[3] is at the Father's[4] side, he[5] has made him[6] known. (John 1:18 ESV)


I have always had trouble understanding what this verse is actually saying, partially because I can't determine which person of the Trinity each noun is associated with.

I've tagged each eligible noun with a number. Please explain which person of the Trinity is associated with which noun and your reasoning for thinking so.
No man has ever seen God[1]; the only-begotten Son[2], who[3] is in the bosom of the Father[4], he[5] has declared [him][6].

θεὸν[1] οὐδεὶς ἑώρακεν πώποτε ὁ μονογενὴς υἱός[2], ὁ[3] ὢν εἰς τὸν κόλπον τοῦ πατρὸς[4] ἐκεῖνος[5] ἐξηγήσατο


[1] the Father
[2] the Son
[3] the Son
[4] the Father
[5] the Son
[6] the Father (pronoun not present in Greek, but the ellipsis is appropriately supplied according to the context)


Basically, it's saying that the only-begotten Son, Jesus, is in the bosom of the Father, at all times. Nobdoy has ever seen the Father. The only-begotten Son "exegeted" or revealed the Father to us. The Greek verb ἐξηγήσατο, a conjuagtion of the lexical form ἐξηγέομαι, is where we get the English noun "exegesis" from.