I think the usual way these verses are shared carries the implication that the Kingdom of God is over there, and we are to set our focus, attention and effort on traveling from here to over there, on the other side of the fence where we find His grass greener and able to provide for our every need. But we need to get there.
There is a different view that I find more theologically sound. Consider…
What is the kingdom of God? “After this, Jesus traveled about from one town and village to another, proclaiming the good news of the Kingdom of God.” (Luke 8:1) What is the kingdom? It is good news. If we have received good news today, it just flows into our tomorrows.
“The kingdom of God is righteous, peace and joy in the Holy Spirit.” (Romans 14:17). If we have these things, our “today” is perfect. We have no need for worry or concern for tomorrow, for we are fully in the present with Him, in Spirit.
When will the kingdom of God come? “One day the Pharisees asked Jesus, “When will the kingdom of God come?” Jesus replied, “The kingdom of God can’t be detected by visible signs…” (Luke 17:20-1) Looking around for evidence of the Kingdom will never reveal it for it is invisible, a mystery. The Kingdom manifests to those open to receive it.”
“Or do you not know that the unrighteous will not inherit the kingdom of God?...” (1 Cor 6:9) The kingdom of God is for today, not sometime in the by-and-by after we’ve died. Only those that are alive are inheritors. They - the alive - inherit because someone else died and left them an inheritance. Jesus died to leave us His inheritance. Today two thousand years after His death we continue to receive our inheritance. He left us righteousness, peace and joy - good news, for today.
Where is the kingdom of God? “You won’t be able to say, ‘Here it is!’ or ‘It’s over there!’ For the Kingdom of God is already among you.” (Luke 17:22) According to Strong’s NT 1787 ἐντός, the kingdom is within you, inside, in the midst of you. And that was written 2,000 years ago.
“But if I cast out demons by the Spirit of God (and He did), then the kingdom of God has come upon you.” (Matthew 12:28) (comment, mine). The kingdom of God has been ours to experience for more than 2000 years.
Who made it possible for us to be in the Kingdom of God? “He made Him who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him.” (2 Corinthians 5:21)
What does the kingdom of God look like? “For the kingdom of God is not just a lot of talk, it is living by God’s power.” (1 Corinthians 4:20).
When did you become righteous? “The Spirit convicts you of righteousness.” John 16:10 This means that the Spirit reminds you, confirms to you, that you ARE righteous. You realize your righteousness when you hear the Spirit remind you.
Do you see the connection?
We are instructed to seek the kingdom of God – given to us as an inheritance by Jesus, the substance of which is good news, righteousness, peace and joy; the power of God within each of us. When we seek and find that the kingdom is within us…when we realize it is ours to behold, to live in and participate in – with Him, we realize that within us is everything we need for life and godliness and we need not worry about tomorrow. For every day of our lives is a today in which we realize our joint righteousness, live in peace and joy and need have no concern for our tomorrows.