Chance,

I've never heard that before:

40 days after the resurrection

I'm not saying that you are wrong, only that I never heard it or considered that.

Acts 1:3 To whom also he shewed himself alive after his passion by many infallible proofs, being seen of them forty days, and speaking of the things pertaining to the kingdom of God:

You caused me to consider that, "being seen of them forty days", doesn't necessarily mean seen every day, consecutively, for 40 days.

I guess there could have been some days when he wasn't seen of them, making the entire period longer than 40 consecutive days.

The other thing is when did Pentecost happen that year?

The LORD gave specific dates for Passover, Unleavened Bread, Feast of Trumpets, Day of Atonement, and Feast of Tabernacles:

Leviticus 23:5 In the fourteenth day of the first month at even is the LORD’S passover.

  6 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.

  24 Speak unto the children of Israel, saying, 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.

  27 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, and offer an offering made by fire unto the LORD.

  34 Speak unto the children of Israel, saying, The fifteenth day of this seventh month shall be the feast of tabernacles for seven days unto the LORD.

However, for Firstfruits, he said:

Leviticus 23:10 Speak unto the children of Israel, and say unto them, When ye be come into the land which I give unto you, and shall reap the harvest thereof, then ye shall bring a sheaf of the firstfruits of your harvest unto the priest:

  11 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.

They didn't harvest on a particular date, but when the plants were ready to harvest.

It doesn't mention the date, or even the month, however, that particular harvest time was generally close to the same time each year in that season.

What is mentioned, is that whenever that harvest was ready, and they reaped the harvest, that they were to bring a sheaf of the firstfruits.

Then, whatever day that was, apparently the priest would wait until morning after that week's sabbath, to wave it.

It doesn't say that it would always be on the morning after the first sabbath after Passover.

Even though many preachers have preached, what they heard other preachers preach, which had heard other preachers preach, ...

For centuries it has been accepted that the feast of Firstfruits must have been the morning after the first sabbath after Passover.

Some say it must be so, because of the pattern of Jesus fulfilling all the spring feasts that year.

However, we should always have the scriptures to determine a pattern, rather than having a pattern determine what the scriptures "should have said".

Also, some say that it was what the Jews practiced at that time.

Well, considering that they rejected their Messiah, I would say that they were not being very scriptural that year, anyway.

Also, considering that the LORD didn't say that they were allowed to change the day,

to change it from the morning after the first sabbath after they reaped the harvest,

to the morning after the first sabbath after Passover.

So, how can we be dogmatic about when Firstfruits was supposed to have been that year?

Then, the LORD said:

Leviticus 23:15 And ye shall count unto you from the morrow after the sabbath, from the day that ye brought the sheaf of the wave offering; seven sabbaths shall be complete:

  16 Even unto the morrow after the seventh sabbath shall ye number fifty days; and ye shall offer a new meat offering unto the LORD.

They were then to wait seven more sabbaths, and then the morning after that was Feast of Pentecost.

The date of Pentecost depended on the date of Firstfruits, which has by tradition, not by scripture, been claimed to have happened,

relative to the date of Passover, rather than relative to the reaping of the season's harvest.

So, all that, along with what you brought out, we cannot tell the date, that year, of his ascension, nor of the date, that year, when he sent the Spirit.

That is similar to not knowing for sure the day that he was born, nor when he will return.

There has even been much debate, over the centuries, on which day of the week that he was crucified.

We certainly see through a glass darkly.

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