According to the Encyclopedia International, article "Week," the days were names for the sun, the moon, and the five visible planets, all of which were associated with pagan deities. The names of the days of the week and their meanings are as follows:

Day

Corresponds To

Sunday

The sun, in honor of the sun god.

Monday

The moon, in honor of the moon god.

Tuesday

The planet Mars, in honor of the god Mars. The Saxons named this day after their god Tiw and called it Tiw's day. "Tuesday" comes from the name of this Saxon god.

Wednesday

The planet Mercury, later named in honor of the Teutonic god Wedn or Woden.

Thursday

The planet Jupiter, later named in honor of the Teutonic god Thor.

Friday

The planet Venus, later named in honor of the Teutonic goddess Frigg or Freia.

Saturday

The planet Saturn, in honor of the Roman god Saturn.

But how did this planetary week come to be so commonly used in the professing Christian world?

Hutton Webster, in his book Rest Days, provides the answer: "The early Christians had at first adopted the Jewish seven-day week with its numbered weekdays, but by the close of the third century AD this began to give way to the planetary week. . . . The use of planetary names by Christians attests the growing influence of astrological speculations introduced by converts from paganism. . . . Thus, gradually a pagan institution was engrafted on Christianity" (emphasis added; see pages 220-221).

This planetary week with its days named after pagan deities is not of God. God Almighty did create the week with seven days, but He merely numbered the days one through seven (Genesis 1:3—2:3). The only day He named was the seventh day, calling it the "Sabbath" (Exodus 16:22-26; 20:8-11).

The names of the months and their meanings are as follows:

Month

From the Latin

January

Januarius, in honor of the Roman god Janus.

February

Februarius, in honor of the Roman festival of general expiation and purification.

March

Martius, in honor of the Roman god Mars.

April

Aprilis, which was derived from aperio, a Latin verb meaning to open. The month is so called because it is the month when the earth opens to produce new fruits.

May

Maius, in honor of the Greek goddess Maia.

June

Junius, in honor of the Roman goddess Juno.

July

Julius, in honor of Roman emperor Julius Caesar.

August

Augustus, in honor of Roman emperor Augustus Caesar.

The rest of the months—September, October, November, December—are derived from the Latin words for the numerals 7, 8, 9, and 10. They were the 7th, 8th, 9th, and 10th months of the old Roman calendar before July and August were inserted ahead of them.

The Hebrew months were originally numbered, but over time names were given to them. For instance, Abib, the first month of spring, means "green [ears of barley]" (this month is also called Nisan, meaning "their flight [out of Egypt]"). Later, the Jews borrowed Babylonian names for many of their months, some of which (e.g., Tammuz) refer to pagan deities.