"Take one day at a time"
"Don't worry about tomorrow".
It is also about obedience.
It is about trust. Do I trust God to look after my future, or do I need to look after myself?
Matthew 6:34,
Therefore do not worry about tomorrow, for tomorrow will worry about itself. Each day has enough trouble of its own.
Psalm 9:10
Those who know your name will trust in you, for you, LORD, have never forsaken those who seek you
Remember when God promised to send manna to the Israelites in the desert, so that they would always have bread to eat? (Exodus 16:1 - 36) Some people didn't believe God would send manna again the next day; they weren't sure they could trust Him, so they gathered extra just in case. The next morning the manna they had collected was crawling with maggots.
Listen to what God said to Moses about the situation. "I will rain down bread from heaven for you. The people are to go out each day and gather enough for that day. In this way I will test them and see whether they will follow my instructions" (Exodus 16:4.)
The people's obedience to God was a measure of their faith in Him. If they followed His instructions, it was proof that they trusted Him.
When Jesus said not to worry about tomorrow was a good command. He knew we would be overwhelmed by the weight of the future (remember the Israelites were in the desert for forty years.) Therefore He instructed us to obey Him today and trust Him for tomorrow.
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