Psalm 100:1
100:1 A Psalm of praise. Make a {a} joyful noise unto the
      LORD, all ye lands.

      (a) He prophecies that God's benefits in calling the
          Gentiles will be so great that they will have
          wonderful opportunity to praise his mercy and rejoice.

Psalm 100:3
100:3 Know ye that the LORD he [is] God: [it is] he [that] hath
      {b} made us, and not we ourselves; [we are] his people,
      and the sheep of his pasture.

      (b) He chiefly means concerning spiritual regeneration, by
          which we are his sheep and people.

Psalm 100:4
100:4 {c} Enter into his gates with thanksgiving, [and] into his
      courts with praise: be thankful unto him, [and] bless his
      name.

      (c) He shows that God will not be worshipped, but by those
          means which he has appointed.

Psalm 100:5
100:5 For the LORD [is] good; his mercy [is] {d} everlasting;
      and his truth [endureth] to all generations.

      (d) He declares that we should never be weary in praising
          him, seeing his mercies toward us last forever.