First, note that he is not making value judgments of them as compared to him. He is describing a process. Death in you allows a gift of life to someone else. Death in them allows a gift of life to a third group, etc. The idea of death in the teacher creating life in the student is the lesson being taught.
The idea here is that Paul is constantly dying - 1 Cor 15.32 ("I die daily") - and it is only through that process of death, of self-denial, that Paul is a suitable vessel for God's power to work through Paul.
As a natural type of this spiritual principle, think of the sacrifices that parents must make in order to create a good life for their child. Their own desires, dreams, wealth, plans, etc, are set aside for the benefit of the child.
But this is just an example in the natural world of a spiritual principle: death works in Paul so that life can work in his spiritual children, the converts in Corinth. This pattern can also be seen in Galatians 2.20 "I am crucified with Christ, nevertheless, I live, yet not I but Christ lives in me.." Paul wants to share that life of Christ with others, but in order to do so, he must be crucified with Christ.
For examples of what it means to be crucified with Christ, take a look at the sacrifices Christ made:
- He did not do anything from his own will, but only from what he saw the Father do - John 5.19
Then answered Jesus and said unto them, Verily, verily, I say unto
you, The Son can do nothing of himself, but what he seeth the Father
do: for what things soever he doeth, these also doeth the Son
- He did not speak anything from himself, except what the Father told him to say - John 12.49
For I have not spoken of myself; but the Father which sent me, he gave
me a commandment, what I should say, and what I should speak.
- He did not judge anyone - John 8.15
Ye judge after the flesh; I judge no man.
- He didn't worry about any aspect of his own life:
Therefore I say unto you, Take no thought for your life, what ye shall
eat, or what ye shall drink; nor yet for your body, what ye shall put
on. Is not the life more than meat, and the body than raiment?
This is just the starting point. Then we can get to "keeping no record of wrongs", etc, and of course willingly laying his life down.
But what all of these have in common is the idea that you do not view your life as your own and are constantly living a life of risk and dependence on the Father. That was required for Paul to do the missionary work that he did so that the Corinthian church could be planted.
With the above in mind, the context of the verse should be easily understood (2 Cor 4.3-12):
For we preach not ourselves, but Christ Jesus the Lord; and ourselves
your servants for Jesus’ sake. For God, who commanded the light to
shine out of darkness, hath shined in our hearts, to give the light of
the knowledge of the glory of God in the face of Jesus Christ. But we
have this treasure in earthen vessels, that the excellency of the
power may be of God, and not of us. We are troubled on every side, yet
not distressed; we are perplexed, but not in despair; Persecuted, but
not forsaken; cast down, but not destroyed; Always bearing about in
the body the dying of the Lord Jesus, that the life also of Jesus
might be made manifest in our body. For we which live are always
delivered unto death for Jesus’ sake, that the life also of Jesus
might be made manifest in our mortal flesh. So then death worketh in
us, but life in you.
Note that Paul is not trying to claim that the principle of the cross only applies to him and not to his hearer. He is trying to educate the hearer, as a father does his children, so they can follow in his footsteps, just as every parent wants to be a grandparent:
2 Cor 12.9-10 (LEB):
And he said to me, “My grace is sufficient for you, because the power
is perfected in weakness.” Therefore rather I will boast most gladly
in my weaknesses, in order that the power of Christ may reside in me.
Therefore I delight in weaknesses, in insults, in calamities, in
persecutions and difficulties for the sake of Christ, for whenever I
am weak, then I am strong.
2 Cor 12.19 (LEB):
Have you been thinking all this time that we are defending ourselves
to you? We are speaking in Christ before God, and all these things,
dear friends, are for your edification.