‘ Then Joshua built an altar to YHWH, the God of Israel in Mount Ebal.'
The next act of Joshua was to fulfil the command of Moses as expressed in Deuteronomy 11:29; Deuteronomy 27:2-3 where God commanded the building of an altar of unhewn stones on Mount Ebal, and the setting up of stones on which the Law of YHWH should be plainly written.
Mount Ebal and Mount Gerizim were two mountains overlooking the plain in which lay Shechem, Mount Ebal to the north and Mount Gerizim to the south. There were no major cities on the regular highway between Bethel and Shechem (see Judges 21:19), although Shiloh lay along the route. There was nothing therefore to prevent the Israelites from making for Shechem along the main highway, a journey of about forty eight kilometres (thirty miles). But the striking fact is that there is no record anywhere in Joshua about the invasion and capture of Shechem, nor of any activity against their king. Yet they were passing through Shechemite territory. Shechem was revealed in the Amarna letters as a powerful confederacy. They were not likely to stand by while Israel held a covenant ceremony on their two mountains.
A further striking fact is that in this passage in Joshua reference is made, in respect of the covenant ceremony to take place there, to ‘as well the stranger as the homeborn' (Joshua 8:33) and to ‘the strangers who walked among them' (Joshua 8:35). Yet in the narrative prior to this, from the moment of leaving Egypt, there has been no reference to such people. All the people who left Egypt had come to be seen as one people. They had all been united within the covenant at Sinai. None were seen as ‘strangers'. Their children were seen as ‘true born' Israelites. Strangers were people who would be welcomed to sojourn among them when they were in the land, and who would be regulated by the Law.
Thus it would seem that there were present at this covenant ceremony those who had not been in Egypt and who had not been at Sinai.
This brings us to the question of Shechem. Who dwelt there, and what was their religion? Shechem was an ancient city situated in the hill country of Ephraim. It was mentioned in the 19th century BC Egyptian execration texts, and excavations show it to have been strongly fortified, covering fourteen acres.
Some time after this Jacob purchased land near Shechem, and, when his daughter was violated, ‘Simeon and Levi', with armed men from their household, tricked the Shechemites and destroyed the Canaanite inhabitants of the city (Genesis 34). It is probable that some from their households would then be allowed, or even required, to settle there, partly as a reward for assisting in the attack, and partly in order to look after Jacob's land rights (Genesis 33:19; Genesis 37:12 compare Joshua 24:32). By marrying the bereaved women they would obtain their land rights as well. We may assume that they introduced the worship of YHWH. They may well have been seen elsewhere as ‘Habiru'. This was probably when the idea of Baal-berith, ‘the lord of the covenant', (Judges 9:4) originated as genuine worship of YHWH, or there may have been a gradual compromise and amalgamating of ideas. Thus Shechem was no longer directly Canaanite.
It was very prosperous in the Hyksos period (1700-1550 BC) during which a massive fortress-temple was built. This may well have been ‘the house of Baal-berith' mentioned in Judges 9.
In the Amarna letters, which were correspondence between the Pharaohs and their vassals in Canaan in the 15th century BC, its king Labayu was said by an enemy (Abdi Heba) to have given Shechem to the Habiru. He refers to ‘-- the sons of Lab'ayu, who have given Shechem to the Habiru.' Labayu and his sons were spasmodically vassals of and rebel leaders against Egypt with influence as far as Gezer and Taanach and who even threatened Megiddo, who wanted a hundred troops to assist in defending against them (‘Let the king give a hundred garrison men to protect the city. Truly Lab'ayu has no other intention. To take Megiddo is that which he seeks!'). Thus it would seem that Shechem contained a large non-Canaaanite section of population at this time. Later there is evidence of specific Israelite occupation, from 11th century BC.
So Habiru (‘Apiru), stateless non-Canaanite peoples, appear to have been settled there in the time of Labayu (see above), uniting with the descendants of the men of Jacob's household. Thus it would appear that when Joshua arrived and was welcomed and found non-Canaanites willing to submit to the covenant, who worshipped ‘the Lord of the covenant', and were willing to recognise Him as YHWH, and had Israelite antecedents, he was probably satisfied to incorporate them into the covenant rather than treating them as Canaanites (consider Joshua 24:23). But it is clear from Judges 9 that their worship was to some extent syncretistic and not the pure Yahwism of Moses (thus there it is equated with Baalism - Judges 8:33). But Joshua may not have realised that.
This would explain the ease of the journey to Shechem through country controlled by the Shechemites, and the fact that they could carry out the covenant ceremony unmolested. It would also explain why no mention is made of the conquest of Shechem and why there were ‘strangers' at the covenant ceremony. We should further note that Shechem was recorded in the genealogies of Israel as a ‘son of Manasseh' (Numbers 26:31), recognising their relationship with Israel.
So we may consider that Joshua and Israel arrived at Shechem, welcomed by the inhabitants, and built the altar of unhewn stones on Mount Ebal, as Moses had commanded.
The Samaritan Pentateuch states that this was on Mount Gerizim, but Ebal is the more difficult reading and the Samaritans worshipped on Mount Gerizim and would be prone to favour it (and we know from elsewhere that they were ready to change the text to suit).
Ebal is the mountain of the curses (Deuteronomy 27:9-13) and it is they which were prominent (Deuteronomy 27:15-26). The erecting of the altar and the plastered stones on this mountain would bring home to Israel with especial force that there were curses resulting from breaking the covenant. They were being reminded of the consequences of disobedience even while they worshipped and ate. But on the mount of cursing there was also blessing. It has been suggested that the remains of a small stone building on Mount Ebal dating from 1240-1140 BC, which contained pottery and the bones of cattle, sheep and goats, may indicate cultic connections.