Psalms 86:15

But thou, O Lord, art a God full of compassion, and gracious, longsuffering, and plenteous in mercy and truth.

Jehovah is compassionate, gracious and good, patient and longsuffering, and abundant in mercy, loving-kindness and truth. This is His true character toward His people, full of compassion and mercy. He had revealed Himself in this character to Israel often, so they were without excuse for losing sight of who He was.

Because the Lord is such, there is every encouragement to trust in Him and to keep believing. That trust means trusting Him rather than people and taking Him at His word. It also means resisting discouragement in trials and continuing on in faith.

Hardness of heart toward others misrepresents this compassionate God. It dishonors His name and gives a false picture of His character to the world.