John 4:24

God [is] spirit, and the ones who worship him must worship in spirit and truth."

2 Corinthians 3:17

Now the Lord is the Spirit, and where the Spirit of the Lord [is, there is] freedom.

Matthew 15:8-9

'This people honors me with their lips, but their heart is far, far away from me,

Philippians 3:3

For we are the circumcision, the ones who worship by the Spirit of God and boast in Christ Jesus and do not [put] confidence in the flesh,

1 Samuel 16:7

But Yahweh said to Samuel, "Do not look at his appearance or at the height of his stature, because I have rejected him. For [God does] not [see] what man sees, for a man {looks on the outward appearance}, but Yahweh {looks on the heart}."

Psalm 51:17

The sacrifices of God [are] a broken spirit; A broken and contrite heart, O God, you will not despise.

Psalm 66:18

If I had considered evil in my heart, the Lord would not have listened.

Isaiah 57:15

For thus says [the] high and lofty one who resides forever, and [whose] name [is] holy: "I reside [in] a high and holy place, and with [the] {contrite} and humble of spirit, to revive [the] spirit of [the] humble, and to revive [the] heart of [the] {contrite}.

Psalm 50:23

He who sacrifices a thank offering honors me, and he [who] orders [his] way; I will show him the salvation of God."

Psalm 50:13-15

Do I eat [the] flesh of bulls or drink [the] blood of goats?

2 Corinthians 1:12

For our reason for boasting is this: the testimony of our conscience that we conducted ourselves in the world, and especially toward you, in holiness and purity of motive from God, not in merely human wisdom, but by the grace of God.

1 Timothy 1:17

Now to the King of the ages, immortal, invisible, to the only God, [be] honor and glory {forever and ever}. Amen.

Treasury of Scripture Knowledge

Summary

God is a Spirit: and they that worship him must worship him in spirit and in truth.

Bible References

A spirit

2 Corinthians 3:17
Now the Lord is the Spirit, and where the Spirit of the Lord [is, there is] freedom.
1 Timothy 1:17
Now to the King of the ages, immortal, invisible, to the only God, [be] honor and glory {forever and ever}. Amen.

Must

1 Samuel 16:7
But Yahweh said to Samuel, "Do not look at his appearance or at the height of his stature, because I have rejected him. For [God does] not [see] what man sees, for a man {looks on the outward appearance}, but Yahweh {looks on the heart}."
Psalm 50:13
Do I eat [the] flesh of bulls or drink [the] blood of goats?
Psalm 51:17
The sacrifices of God [are] a broken spirit; A broken and contrite heart, O God, you will not despise.
Psalm 66:18
If I had considered evil in my heart, the Lord would not have listened.
Isaiah 57:15
For thus says [the] high and lofty one who resides forever, and [whose] name [is] holy: "I reside [in] a high and holy place, and with [the] {contrite} and humble of spirit, to revive [the] spirit of [the] humble, and to revive [the] heart of [the] {contrite}.
Matthew 15:8
'This people honors me with their lips, but their heart is far, far away from me,
2 Corinthians 1:12
For our reason for boasting is this: the testimony of our conscience that we conducted ourselves in the world, and especially toward you, in holiness and purity of motive from God, not in merely human wisdom, but by the grace of God.