Summary: He must increase, but I must decrease.
HE WHO COMES FROM ABOVE.
John’s disciples came to him with the observation, ‘The One of whom you testified is baptising, and all men come to Him’ (cf. John 3:26). ‘All men’ might have been an exaggeration, but Jesus was making more disciples than His forerunner (cf. John 4:1-2). John’s response was one of humility, culminating in the words, ‘He must increase, but I must decrease’ (cf. John 3:30).
Jesus is “from heaven” (cf. John 3:13).
“No man receives His testimony” seems to rebuke John’s disciples’ earlier exaggeration, ‘all men come to Him’ (cf. John 3:26). Both, perhaps, can be viewed as hyperbole. This need not be taken too literally, as the next verse shows.
JOHN 3:33. “He that receives His testimony” metaphorically “seals” the fact that “God is true” (cf. Romans 3:4). God is true to His word. God is true to His promise. Thus do I believe ‘the record that God gave of His Son,’ and would happily confirm it with my signature (cf. 1 John 5:10).
“Speaks the words of God” (cf. Deuteronomy 18:18).
“For God gives not the Spirit by measure unto Him.” Earlier prophets only had ‘a measure’ of the Spirit, and that only for a limited time or function; whereas Jesus, being the One ‘in whom dwells the fulness of the Godhead bodily’ (Colossians 2:9) already has the fulness of the Spirit (cf. Isaiah 11:2).
“And has given all things into His hand.” He has all things pertaining to our salvation (cf. John 17:2). He has the keys of death and hell (cf. Revelation 1:18). He has all authority, and commissions us to go out into all the world (cf. Matthew 28:18-20).
JOHN 3:36. “He who believes on the Son has everlasting life.” Not ‘pie in the sky when I die’, but a fulness of life for all eternity already begun - for the believer, at the point of believing - in this realm of time (cf. John 3:16). To believe is to ‘pass from death to life’ (cf. John 5:24).
“And he who believes not the Son shall not see life.”
The Greek word usually translated “believes not” here in John 3:36 is not simply a negation of ‘believe’ (as in John 3:18). It is a stronger word, implying an unbending refusal to believe. The same word is translated elsewhere as ‘disobeying’ (Cf. Romans 10:21).
“But the wrath of God abides on him.” This takes us right back to the beginning of the chapter: ‘Except a man be born again he cannot see the kingdom of God’ (cf. John 3:3). There is no other way.
‘He that has the Son has life; he that has not the Son of God has not life. These things I have written unto you that believe on the name of the Son of God; that you may know that you have eternal life’ (1 John 5:13).