Leviticus 23
These are my feasts.
The chapter begins with the weekly Sabbath and then names the appointed times in their seasons. Wake Up Call keeps these days. We do not keep feast days that the Torah does not name.
Passover, Unleavened Bread, Firstfruits, Weeks, Trumpets, the Day of Atonement, Tabernacles, and the Eighth Day are proclaimed because they are written. Each one is a holy convocation.

Leviticus 23:3
The Weekly Sabbath
The seventh day
Six days shall work be done: but the seventh day is the sabbath of rest, an holy convocation; ye shall do no work therein: it is the sabbath of the LORD in all your dwellings.
The assembly rests and gathers on the seventh day. It is the first appointed time named in Leviticus 23.

Leviticus 23:5
Passover
Fourteenth day of the first month, at even
In the fourteenth day of the first month at even is the LORD's passover.
We keep Passover on the day the Torah names, at twilight, and we do not move it to another season.

Leviticus 23:6
Unleavened Bread
Fifteenth through the twenty-first day of the first month
And on the fifteenth day of the same month is the feast of unleavened bread unto the LORD: seven days ye must eat unleavened bread.
Seven days of unleavened bread follow Passover. The first day and the seventh day are holy convocations.

Leviticus 23:11
Firstfruits
The morrow after the Sabbath
And he shall wave the sheaf before the LORD, to be accepted for you: on the morrow after the sabbath the priest shall wave it.
The sheaf is waved on the morrow after the Sabbath, just as the chapter is written.

Leviticus 23:16
The Feast of Weeks
Fifty days from the day of the sheaf
Even unto the morrow after the seventh sabbath shall ye number fifty days; and ye shall offer a new meat offering unto the LORD.
Weeks is counted from the sheaf: fifty days, to the morrow after the seventh Sabbath.

Leviticus 23:24
Trumpets
First day of the seventh month
In the seventh month, in the first day of the month, shall ye have a sabbath, a memorial of blowing of trumpets, an holy convocation.
A memorial of blowing of trumpets, and a day of rest.

Leviticus 23:27
The Day of Atonement
Tenth day of the seventh month
Also on the tenth day of this seventh month there shall be a day of atonement: it shall be an holy convocation unto you; and ye shall afflict your souls.
A holy convocation. The Torah says to afflict your souls and to do no work.

Leviticus 23:34
Tabernacles
Fifteenth day of the seventh month, for seven days
The fifteenth day of this seventh month shall be the feast of tabernacles for seven days unto the LORD.
Seven days of dwelling in booths, a holy convocation on the first day.

Leviticus 23:36
The Eighth Day
The day following the seven days of Tabernacles
On the eighth day shall be an holy convocation unto you. It is a solemn assembly; and ye shall do no servile work therein.
The chapter closes the feast with an eighth day, a solemn assembly. We keep that day too, because it is written.
The sermons that open these days are kept for baptized members.