2 Thessalonians 2:13

But we ought always to give thanks to God for you, brethren beloved of the Lord; because God hath from the beginning chosen you to salvation, through sanctification of the Spirit, and belief of the truth:

Titus 1:2

in hope of eternal life, which God, who cannot lie, promised before all ages;

Hebrews 6:13

For when God made the promise to Abraham, because He could swear by no greater, He sware by Himself, saying,

Hebrews 6:17

Wherefore God being willing more abundantly to manifest unto the heirs of the promise the immutability of his counsel, confirmed it with an oath:

Treasury of Scripture Knowledge

Summary

Once have I sworn by my holiness that I will not lie unto David.

That i will not lie

Bible References

Once

Hebrews 6:13
For when God made the promise to Abraham, because He could swear by no greater, He sware by Himself, saying,

That i will not lie

2 Thessalonians 2:13
But we ought always to give thanks to God for you, brethren beloved of the Lord; because God hath from the beginning chosen you to salvation, through sanctification of the Spirit, and belief of the truth:
Titus 1:2
in hope of eternal life, which God, who cannot lie, promised before all ages;