Psalm 100:1-4 Make a joyful noise unto the LORD, all ye lands.
Serve the LORD with gladness: come before his presence with singing.
Know ye that the LORD He is God: it is He that hath made us, and not we ourselves; we are His people, and the sheep of His pasture. Enter into His gates with thanksgiving, and into His courts with praise: be thankful unto Him, and bless His name.
Verse 5: For the LORD is good; His mercy is everlasting; and His truth endureth to all generations.
We should start by reading verse 5 first. For once we get a revelation of this verse, will we freely, out of our own heart and not as an act of obedience, do verses 1 thru 4.
The revelation I am referring to is a deeper understanding of the Hebrew in this text.
Psalm 100:5 For the Lord is GOOD (Hebrew word for good is"tob": meaning bountiful, cheerful, at ease, (causes us to be in) favour, graciously, joyful, kindly, (full of) kindness, merry, most, pleasant, (full of) pleasure, precious, prosperity, sweet, wealth, welfare, (be) well ([-favoured]).
His MERCY is everlasting (Hebrew word for mercy "chesed" meaning (His) kindness; piety (loyal reverence to a person or thing) beauty: - favour, good deed (-liness, -ness), kindly, (loving-) kindness, merciful (kindness),
His TRUTH endureth to all generations. Truth is the Hebrew word "emunah" meaning firmness, security, moral fidelity (the quality or state of being faithfull; exactness), faithfulness, stable, steady.
So, in context, we could read verse 5 this way:
Psalm 100:5 For the Lord is bountiful, cheerful and at ease toward us, He causes gracious favor to be upon us because He is kind, most pleasant; full of pleasure and prosperity. His mercy, His loyal reverence to His children and His loving-kindness is everlasting, without end. His truth; that is His firmness, His security His quality or state of being faithful to us; His exactness) in being stable and steady endures to all generations.
And with this understanding we will :
Make a joyful noise unto the LORD, all ye lands. Serve the LORD with gladness: come before his presence with singing. Know ye that the LORD He is God: it is He that hath made us, and not we ourselves; we are His people, and the sheep of His pasture. Enter into His gates with thanksgiving, and into His courts with praise: be thankful unto Him, and bless His name.
So be it.