Luke 15:6

and coming home, he calleth his friends and neighbors together and saith unto them, Rejoice with me, for I have found my sheep which was lost.

John 15:11

These things have I spoken unto you, that my joy in you may continue, and that your joy may be full.

2 Corinthians 8:3

For to their power, I bear them witness, yea and beyond their power, they contributed of their own accord:

2 Corinthians 8:12

For if there be first a willing mind, any me is accepted according to what he hath, not according to what he hath not.

2 Corinthians 9:7-8

Let every one give as he chuses in his own heart; not with reluctance, or constraint: for God loveth a chearful giver.

Philippians 4:10

I rejoiced greatly in the Lord, that your care for me has now flourished again; for whom ye were indeed careful before, but ye wanted opportunity.

1 Thessalonians 3:6-9

But now Timothy being come back to us from you, and having brought us good tidings concerning your faith and love, and that ye have always a good remembrance of us, greatly desiring to see us, as we indeed do to see you;

Philippians 2:15-17

that ye may be blameless and inoffensive, the children of God without reproof, in the midst of a crooked and perverse generation; among whom ye shine as lights in the world,

Philippians 4:1

Wherefore, my brethren, beloved and much desired, my joy and crown, so stand ye fast in the Lord, my beloved.

Treasury of Scripture Knowledge

Summary

Then the people rejoiced, for that they offered willingly, because with perfect heart they offered willingly to the LORD: and David the king also rejoiced with great joy.

Bible References

They offered

2 Corinthians 8:3
For to their power, I bear them witness, yea and beyond their power, they contributed of their own accord:
2 Corinthians 9:7
Let every one give as he chuses in his own heart; not with reluctance, or constraint: for God loveth a chearful giver.

David

Luke 15:6
and coming home, he calleth his friends and neighbors together and saith unto them, Rejoice with me, for I have found my sheep which was lost.
John 15:11
These things have I spoken unto you, that my joy in you may continue, and that your joy may be full.
Philippians 2:15
that ye may be blameless and inoffensive, the children of God without reproof, in the midst of a crooked and perverse generation; among whom ye shine as lights in the world,
Philippians 4:1
Wherefore, my brethren, beloved and much desired, my joy and crown, so stand ye fast in the Lord, my beloved.
1 Thessalonians 3:6
But now Timothy being come back to us from you, and having brought us good tidings concerning your faith and love, and that ye have always a good remembrance of us, greatly desiring to see us, as we indeed do to see you;