The apostle returned to his earlier contrast between words and real power ( 1 Corinthians 2:1-5). Real power is the power of the Holy Spirit working through humble messengers. The kingdom of God here does not refer to the future millennial kingdom alone but to God"s rule over all, including His people in the church now, as the context clarifies. [source][source][source]
The relationship between the Apostle and his converts was very tender. They were his children. They might have instructors and tutors, but they could have but one father; and as father he might have to use the rod. Love can be stern and punitive. Spare the rod and spoil the child. It is not pure but selfish love that forbears to speak and act strongly when eternal interests are at stake. This is an aspect of God's love which is likely to be overlooked. If we escape chastisement, we are bastards and not sons. "What son is he whom the father chasteneth not?" Hebrews 12:5-11.
The beloved Timothy was sent to bring the recreant church back to its old love and faith. He was well fitted to represent the Apostle till Paul could tear himself from his thronging duties at Ephesus. Notice that God's kingdom comes in power, not in word, 1 Corinthians 4:21. Is not this the reason why it comes so slowly? We treat it as though it would come through our much speaking, through eloquent and honeyed speech. But it is not so. It comes in the power of the Holy Spirit, and in that supremacy of the Divine Spirit over all other spirit forces. God send us more of this great dynamic! [source]
Chapter Summary: 1 Corinthians 4
1In what account the apostles ought to be regarded 7We have nothing which we have not received 9The apostles spectacles to the world, angels, and men; 13the filth and offscouring of the world; 15yet our fathers in Christ; 16whom we ought to follow
What do the individual words in 1 Corinthians 4:20 mean?