John 4
22 Ye worship ye know not what: I know what we worship: for salvation is of the Jews.
23 But the hour cometh, and now is, when the true worshippers shall worship the Father in spirit and in truth: for the Father seeketh such to worship him.
24 God is a Spirit: and they that worship him must worship him in spirit and in truth.

D&C 93
19 I give unto you these sayings that you may understand and know how to worship, and know what you worship, that you may come unto the Father in my name, and in due time receive of his fulness.

D&C 93:8-14
8 Therefore, in the beginning the Word was, for he was the Word, even the messenger of salvation—
9 The light and the Redeemer of the world; the Spirit of truth, who came into the world, because the world was made by him, and in him was the life of men and the light of men.
10 The worlds were made by him; men were made by him; all things were made by him, and through him, and of him.
11 And I, John, bear record that I beheld his glory, as the glory of the Only Begotten of the Father, full of grace and truth, even the Spirit of truth, which came and dwelt in the flesh, and dwelt among us.
12 And I, John, saw that he received not of the fulness at the first, but received grace for grace;
13 And he received not of the fulness at first, but continued from grace to grace, until he received a fulness;
14 And thus he was called the Son of God, because he received not of the fulness at the first.

John 4:6
6 Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me.

“Behold, I come unto my own, to fulfil all things which I have made known unto the children of men from the foundation of the world, and to do the will, both of the Father and of the Son—of the Father because of me, (the spirit of truth), and of the Son because of my flesh. And behold, the time is at hand, and this night shall the sign be given.” - 3 Nephi 1:14

John 14:16-20
16 And I will pray the Father, and he shall give you another Comforter, that he may abide with you for ever;
17 Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you.
18 I will not leave you comfortless: I will come to you.
19 Yet a little while, and the world seeth me no more; but ye see me: because I live, ye shall live also.
20 At that day ye shall know that I am in my Father, and ye in me, and I in you.

D&C 93
2 And that I am the true light that lighteth every man that cometh into the world;
3 And that I am in the Father, and the Father in me, and the Father and I are one—
4 The Father because he gave me of his fulness, and the Son because I was in the world and made flesh my tabernacle, and dwelt among the sons of men.

D&C 93
26 The Spirit of truth is of God. I am the Spirit of truth, and John bore record of me, saying: He received a fulness of truth, yea, even of all truth;
...
66 Behold, that which you hear is as the voice of one crying in the wilderness—in the wilderness, because you cannot see him—my voice, because my voice is Spirit; my Spirit is truth; truth abideth and hath no end; and if it be in you it shall abound.