Trust in the Lord with all your heart, and do not lean on your own understanding. In all your ways acknowledge him, and he will make straight your paths.
Proverbs 3:5-6 (ESV)
When we rely on our own understanding, we tend to trust our own knowledge and discernment to sustain us throughout life. If we can look at Jeremiah 17:9, it tells us that we cannot rely on our own sinful nature.
Trusting the Lord with all our heart means that we cannot place our own right to understand above His right to direct our lives as He sees it. All our knowledge, our wisdom and our will must tend towards that of God. We must carefully connect and pursue God's will for our lives and do things God's way instead of our way.
As believers, we need to know that trusting our Lord means more than believing in who He is. God created us, He knows us more than we know ourselves. He is an all-knowing God and from there he has the ability to see what lies ahead of us and because of that he knows what we need to fully be the person he created us.
As we place our trust in God to do His will, let us dedicate ourselves to seeking Him and trusting Him in all circumstances.