THE FIRST NOEL まきびとひつじを

Joy to the world もろびとこぞりて in Japanese

This is the best version I could find so if you come across something better  leave a comment and let me know.

I found lyrics here

Moro-bito kozorite, mukae-matsure!
Hisashiku machinishi, Shu wa kimaseri,
Shu wa kimaseri, Shu wa, Shu wa kimaseri.

Akuma no hitoya wo, uchi-kudakite,
Toriko wo hanatsu to, Shu wa kimaseri,
Shu wa kimaseri, Shu wa, Shu wa kimaseri.

Kono yo no yami-ji wo, terashi-tamu,
Tae-naru hikari no, Shu wa kimaseri,
Shu wa kimaseri, Shu wa, Shu wa kimaseri.

Shibomeru kokoro no, hana wo sakase,
Megumi no tsuyu oku, Shu wa kimaseri,
Shu wa kimaseri, Shu wa, Shu wa kimaseri.

Heiwa no kimi naru, Miko wo mukae,
Sukui no nushi to zo, home-tataeyo,
home-tataeyo, home, home-tataeyo!

Silent Night きよしこのよる in Japanese

This is the best version I could find so if you come across something better  leave a comment and let me know.

Here are the lyrics I found here

Kiyoshi kono yoru hoshi wa hikari
sukui no miko wa mabune no naka ni
nemuri tamo-o. itoyasuku.

Kiyoshi kono yoru mitsuge ukeshi
makibitotachi wa miko no mimae ni
nukazukinu, kashikomite.