Trust is having confidence in someone but Trust in God means absolute dependence on God and in God. You can't trust whom you don't believe in.

The reason why we call someone trustworthy means such persons have proven to be firm, loyal, honest over the years of meeting such persons.

God is our creator , We are all His creation. If you don't trust your Creator, who do you want to trust as His creation.
If you , the clay do not trust the Potter( God) then who are you going to trust?

"Trust in the Lord and lean not on your own understanding, In all your ways, acknowledge him and He will direct your paths."
Proverbs 3:5-6

Oftentimes we lean on our understanding, strength, intellect and skills more than trusting in God

TRUST IN THE WORD OF GOD - How much do you know what the Bible is saying about you, your life, your situation?
How much do you know the purpose of God for you on this earth?
How much do you study and meditate on his word?

The entrance of His word gives light that is, illumination, understanding and wisdom.

"For the word of God is quick, and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and...