As a royal priest Solomon led the nation of priests in making an immense sacrifice to Yahweh. The sacrifices were all offerings of worship. The burnt offering represented the dedication of the worshipper's person to God. The grain offering pictured the dedication of his work to God. The peace offering expressed the joy that resulted from the fellowship God had made possible with Himself and with the worshipper's fellowman (Lev. 1-3).
The number of offerings seems incredibly large, but contemporary extrabiblical records of other sacrifices that involved thousands of animals are extant. Perhaps the priests made sacrifices at other places outside the temple courtyard. People came from the far Northeast (Hamath) and the extreme Southwest (the Wadi el-Arish) to this feast. Solomon extended the celebration an extra week (v. 65).
Verse 66 is very significant because it shows that because of Israel's rededication in this covenant renewal ceremony King Solomon enjoyed blessing from his people on whom he had brought blessing. The result was joy and gladness of heart for everyone. These are what God had promised in the Mosaic Law as consequences of commitment to His will. God blessed Solomon personally, and he became a channel of blessing to the nation he served because he committed himself to obeying God's Word.
This was the biggest event in Israel, in terms of its theological significance, since God gave Israel the Law at Mount Sinai. Israel was finally in the Promised Land with her God enthroned in a place of great honor. Now Israel was in position to fulfill her calling as a nation in the world as never before in her history (cf. Exod. 19:5-6).95