2 Samuel 24:1
‘Now the anger of the LORD burned against Israel again, and He incited David against them to say, “Go, count Israel and Judah.”’
This was sinful for David to count Israel. The purpose was to know their military might. The problem was that they were to trust God for their defense. It was fine that they had an army and that they trained and prepared for war, but in the end, they were to trust God.
David knew this. He said in Psalm 33:16, "The king is not saved by a mighty army; A warrior is not rescued by great strength." The census was putting trust in horses and vast armies.
We can have similar temptations. We should go to doctors and take medicine. However, our trust should be in God. We should study and be prepared for tasks in life. However, we should trust God in the process. We will be presented with situations for the rest of our lives which present us with the choice to trust Him.
Some times we aren't to perform some actions as it would be trusting ourselves and our resources. I will often wrestle with this and giving money. I know what my bills are and when they are due. The tithe is always an inconvenience. I have to trust Him and pay it, knowing He will help with the expenses.
Proverbs 3:5,6 is key to trusting God. "Trust in the Lord with all your heart, lean not on Your own understanding. In all your ways acknowledge Him and He will direct your paths." The problem is leaning on our own understanding. It's natural; we've been doing it all our lives. When it comes to God, at times we need to put aside our understanding. The old hymn says, "Trust and obey. There is no other way to be happy in Jesus, but to trust and obey."
Lord, help us to trust You, not to lean on our own understanding.