6:14 I will destroy them with the earth, but make thee an ark - I will take care to preserve thee alive. This ark was like the hulk of a ship, fitted not to sail upon the waters, but to float waiting for their fall. God could have secured Noah, by the ministration of angels without putting him to any care or pains, but he chose to employ him in making that which was to be the means of his preservation, both for the trial of his faith and obedience, and to teach us that none shall be saved by Christ, but those only that work out their salvation; we cannot do it without God, and he will not without us: both the providence of God and the grace of God crown the endeavours of the obedient and diligent. God gave him particular instructions concerning this building. It must be made of Gopher - wood; Noah, doubtless, knew what sort of wood that was, though now we do not. He must make it three stories high within: and, He must divide it into cabins with partitions, places fitted for the several sorts of creatures, so as to lose no room. Exact dimensions are given him, that he might make it proportionable, and might have room enough in it to answer the intention, and no more. He must pitch it within and without: without, to shed off the rain, and to prevent the water from soaking in; within, to take away the ill smell of the beasts when kept close. He must make a little window towards the top to let in light. He must make a door in the side of it by which to go in and out.
6:12-21 God told Noah his purpose to destroy the wicked world by water. The secret of the Lord is with them that fear him, Ps 25:14. It is with all believers, enabling them to understand and apply the declarations and warnings of the written word. God chose to do it by a flood of waters, which should drown the world. As he chooses the rod with which he corrects his children, so he chooses the sword with which he cuts off his enemies. God established his covenant with Noah. This is the first place in the Bible where the word 'covenant' is found; it seems to mean, 1. The covenant of providence; that the course of nature shall be continued to the end of time. 2. The covenant of grace; that God would be a God to Noah, and that out of his seed God would take to himself a people. God directed Noah to make an ark. This ark was like the hulk of a ship, fitted to float upon the waters. It was very large, half the size of St. Paul's cathedral, and would hold more than eighteen of the largest ships now used. God could have secured Noah without putting him to any care, or pains, or trouble; but employed him in making that which was to be the means to preserve him, for the trial of his faith and obedience. Both the providence of God, and the grace of God, own and crown the obedient and diligent. God gave Noah particular orders how to make the ark, which could not therefore but be well fitted for the purpose. God promised Noah that he and his family should be kept alive in the ark. What we do in obedience to God, we and our families are likely to have the benefit of. The piety of parents gets their children good in this life, and furthers them in the way to eternal life, if they improve it.
