V.1-3 David hasn’t forgotten the Ark.
V.4-15 We saw in the 13th chapter that David had disobeyed God’s plain instructions about the carrying of the Ark, and the result. Now he is very careful to have the proper men appointed to do the carrying — the Levites (See Num. 4:4-15).
V.16-28 David looks after every detail. All must be according to the Word of God. If David had not made his mistake the first time, he might not have become so interested in the Levites, and their being appointed as singers. Isn’t it wonderful that the Lord often brings blessing out of our failures!