We really have to go back to Exodus 19 and go through the entire chronology or sequence of Moses to get a clear picture of what is going on. In short, the Charleton Heston sequence of events is woefully simplistic and in a word, wrong. Moses actually ascends and descends the mountain a number of times, and the order in which things happen are often misrepresented in lessons for children and even adult media.
There are in fact as many as 6 ascents and descents and at least 5.
However, (ironically?) of the 5-6 ascents, the instance of Ex. 24:9-14 referenced in the question does NOT contain two of them.
Summary of Ascents
- Ex. 19:3 Moses goes up and receives a message from the Lord.
- Ex. 19:9 Moses reports to the Lord after telling the people the Lord's message. Moses then "went down" in v14 after hearing the Lord's instructions, meaning he must have "went up" in v9
- Ex 19:20 The Lord calls Moses to the top of the mountain. Went down in v25
- Ex. 20:21 Moses goes at least partially up the mountain (past the boundaries) enough to be near the thick darkness/cloud where God was. Comes down in Ex 24:3. (Unless this is a tent meeting we read about in Ex 33:9-11)
- Ex. 24:9 Moses, Aaron, Nadab, Abihu and 70 elders go up the mountain but not all the way to God (see instructions in 24:1-2) Moses goes the rest of the way up in 24:12-13,15. He comes down 40 days later in 32:15.
- Ex. 34:4 Moses bring the new tablets up. Comes down in v29.
1) Arrival at Sinai
Exodus 19 has the Israelites arriving at Mt. Sinai.
The first "went up" we have is here in 19:3.
I confess, I am no Hebrew scholar so so I cannot attribute any meaning to the usage of the forms of "went up" to God, to the LORD, or to the mountain, etc, used throughout the next few chapters. I will, however, note which is used where.
I can say that "went" here is 'alah which from what I can find is universally seen as a upward going. It can be "went" or "come" or "go" but it nearly always has an "upward" element.
So Moses went up to God and was called to from the mountain. God offers a shortened version of the covenant he is to make with the people. Moses comes down in 19:7 and relays this offer to the people and they reply that they will agree to it.
2) Preparing for God's
Moses goes to report the people's answer and God tells Moses his plan to reveal himself to the people. He gives instructions on how to prepare and be ready for the third day. Moses went down the mountain in v14, and relays the instructions to the people. They are to wait until the long trumpet blast and then come up 'alah to the mountain. Not up the mountain itself, as context in 19:16 shows that they did not go up the mountain itself, but rather went up from the camp to the foot of the mountain where they waited in v17.
Of note here is the first use of "went down" at Sinai. This is yarad and it means to go down, essentially the opposite of 'alah.
3) The people wait at the mountain
On the third day out of the thunder, lightning and thick cloud comes the long trumpet blast. The people leave the camp and come to the foot of the mountain, up to the boundary markers.(v16)
Moses is called up the mountain in 19:20 and he "went up" ('alah). God repeats the warning for the people not to come up ('alah) the mountain.
Moses is told to go down (yarad) and bring Aaron back up ('alah) with him. Moses goes down in v25.
4) God Speaks and the people are terrified
Now whether you believe God speaks directly to the people here, or whether you believe this is Moses speaking the words God spoke to him (as Ex. 19:25 would suggest) doesn't change the goings up and down.
We should also note at this point Moses has not yet completed the command to bring Aaron up.
The people become afraid of the thunder, lightning, trumpets, and smoke and ask Moses to mediate for them.
Moses draw near to the thick darkness where God is in 20:21. We do not know if Aaron with him or whether that command is completed in the next ascent.
God begins to tell Moses what to say to the people in 20:22, and it is reiterated in 21:1.
When we finally get to 24:1 we must understand this is still God speaking to Moses. This is not a narrative, but rather it is instruction for what to do after telling the people all that he just told Moses.
It is my opinion that this is not an ascent and descent, but rather God speaking to Moses through the cloud, possibly at Moses' tent as we read happened later in 33:9-11, or at least at the foot of the mountain which the cloud is covering. I believe this because the verbiage changes. Moses "draws near" in 20:21 instead of "going up" ('alah). Also, he then goes to tell the people what he has been told in 24:3 but it is not "go down" yarad but simply a basic verb for come/go/enter (bow') with no directional reference (except maybe "in"), be it up or down. Also this clarifies the confusion over the command to bring Aaron next time Moses goes up. If this is not an ascent then we see that the next time Moses goes up, he does indeed bring Aaron and so he is faithful to God's command.
I have included it as a possible ascent/descent because at this point in the story the dark cloud has been described as on the mountain, so in drawing near to it one could interpret Moses as going up the mountain.
If you do view this as an ascent and descent then it would be precedent for an "implied" ascent and would therefore support the possibility of other implied ascents, such as reading two ascents in 24:9-14.
5) Moses and the others go up the mountain
So Moses tells what God told him to the people and they agree. This time Moses writes it all down (24:4) in what is apparently referred to as the Book of the Covenant(24:7).
Moses reads it again, this time in front of their new altar in what seems a much more formal setting (altar, sacrifices, covenant). After sprinkling the altar and the people with the blood of the sacrifices Moses heads up the mountain.
Now we must remember that God gave Moses specific instructions in 24:1-2 about how he was to bring Aaron and the others up the mountain. We see these commands being followed closely in 24:9. Moses is bringing the exact people he was told to bring in v1 (and including Aaron as instructed in 19:24). Then Moses alone (but with Joshua?) goes up to the Lord in v12 just as he was told in v2 to leave the others.
When we understand 24:9-14 through the context of 24:1-2 it becomes clear this is one ascent, but Aaron and the others do not go all the way up.
Also it should be noted that while v13 says that Moses and Joshua go up, v14 can be understood as Moses' parting words as he and Joshua go up. Not as a separate event.
Many commentaries arrive at the same conclusion, including the Pulpit Commentary, Gill's Exposition. Others seem to reach the same conclusion, but not with any specific commentary.
Others such as the Jamieson-Fausset-Brown Bible Commentary only speak on Aaron and the elders waiting halfway up while Moses and Joshua continue, but say little about the events that follow.
24:15-18 Went up...again?
The next question is how do we understand 24:15-18? Is Moses on the mountain 6 more days after leaving the others and going up alone (but also with Joshua) and then called even farther up the mountain on the seventh day (now truly alone) where he then stays for 40 more days? Or is this once again a separate ascent after the events of 24:14?
If we understand it as a continuance of the ascent of 24:14, as the plain reading would suggest, it seems the key is Joshua. Moses was supposed to come near to the Lord alone (24:2) so when Moses leaves the others to ascend even higher one would think he was go alone, but he brings Joshua with him. This, combined with an additional call up the mountain, suggests that the ascent of 24:13,15 with Joshua was not the final ascent alluded to in 24:2. If it was, Moses should have been alone.
So when Moses alone is called out of the cloud and he goes up to enter it in v18 he is leaving Joshua behind and fulfilling God's instructions perfectly.
Rashi suggests one needs 6 days of seclusion before entering the Shechinah glory:
It teaches you that whoever enters the camp of the Shechinah requires six days separation [seclusion from society] (Yoma 3b).
Whether Moses was on the mountain for 40, 46 or 47 days has been under debate for a long time as Rashi even comments. The summary of these events in Deut 9:9 only mentions the 40 days.
When did the others return?
Moses' parting comments to the others before going on with Joshua in 24:14 can be viewed as implying they are to return to the people. Afterall, Aaron and Hur are instructed to judge over any disputes in Moses' stead. Moses creates a system of governance in Exodus 18. Lesser disputes are handled by the able men Moses chose and any greater disputes were brought to Moses.
If Moses expects to gone for a while, or is unsure how long it will be (or if he will return at all) then no one would be in place to hear the greater disputes. Many think this is the job he is giving to Aaron and Hur while he is gone. This, of course, would require they return to the people.
However, Moses also tells them to "wait here". Many commentaries (Rashi, conclude this is referring to all the people, that they are to camp at the mountain until Moses returns.
It is purely conjecture, but one must wonder what became of Joshua after Moses was called up on the seventh day? Is it not quite possible he came down the mountain to Aaron and the others and then with no other instructions (except to judge the people) they all returned to the camp together.
Nevertheless, we see in Exodus 32:1 that while Moses is still gone Aaron is with the people. They don't know what has become of Moses (the mount was covered in fire for six days afterall) and they have brought their concerns to Aaron. This confirms that Aaron was placed in charge of the people's major disputes.
in the first passage they have all gone up the mountain, and then all returned to the camp, so in this next passage, Moses is speaking to the leaders in the camp, or
are we to understand that in the first passage they never went to the top of the mountain, but maybe half way, and now Moses is telling them to return to the camp? (John Piper)
It is my conclusion that there is only one ascent in the passages in question (24:9-14) when you consider God's instruction in 24:1-2 just as John Piper also concludes.
In case it is unclear, the reason I go through all the ascents is to show the pattern for each ascent. There is always a 'alah and a yarad in the three certain ascents/descents prior to Exodus 24 (except for the first ascent in 19:3, where there is just bow' in 19:7). When you follow this pattern into chapter 24 we see several uses of 'alah in the account but never yarad or even a bow'. This combined with the nearly universal acceptance of Moses going up with Joshua part ways before going on alone as precedent would suggest the same applies to Aaron and the others first before they separate.
Full disclosure: I purposely avoided Piper's commentary while working through this until I had arrived at a conclusion, so as to not be possibly influenced. His conclusions and their support echo my own as well as the other commentaries I referenced.