The candlestick represents the light of God's word and Spirit, in and through Christ Jesus, afforded in this dark world to his believing people, to direct their worship and obedience, and to afford them consolations.
The church is still dark, as the tabernacle was, in comparison with what it will be in heaven; but the word of God is a light shining in a dark place, 2Pe 1:19, and a dark place indeed the world would be without it.
In verse 40 is an express caution to Moses. Nothing was left to his own fancy, or to that of the workmen, or the people; but the will of God must be observed in every particular. Christ's instruction to his disciples, Mt 28:20, is like this, Observe all things whatsoever I have commanded you.
Let us remember that we are the temples of the Holy Ghost, that we have the law of God in our hearts, that we are to live a life of communion with God, feast on his ordinances, and are the light of the world, if indeed we are followers of Christ.
May the Lord help us to try ourselves by this view of religion, and to walk according thereto.