'Certain' in the Bible

When Pharaoh heard about this event, he sought to kill Moses. So Moses fled from Pharaoh and settled in the land of Midian, and he settled by a certain well.

Meanwhile, the seven daughters of a certain Midianite priest would come to draw water in order to fill water troughs for their father's sheep.

And I am certain that the king of Egypt will not let you go without being forced.

And Moses, answering, said, It is certain that they will not have faith in me or give ear to my voice; for they will say, You have not seen the Lord.

So that they may be certain that the Lord, the God of their fathers, the God of Abraham, of Isaac, and of Jacob, has been seen by you.

And I will take you to be my people and I will be your God; and you will be certain that I am the Lord your God, who takes you out from under the yoke of the Egyptians.

{And so it was on a certain day} Yahweh spoke to Moses in the land of Egypt.

So the Lord says, By this you may be certain that I am the Lord; see, by the touch of this rod in my hand the waters of the Nile will be turned to blood;

But as for you and your servants, I am certain that even now the fear of the Lord God will not be in your hearts.

Then said the LORD unto Moses, Behold, I will rain bread from heaven for you; and the people shall go out and gather a certain rate every day, that I may prove them, whether they will walk in my law, or no.

Now I am certain that the Lord is greater than all gods, for he has overcome them in their pride.

If then I have grace in your eyes, let me see your ways, so that I may have knowledge of you and be certain of your grace; and my prayer is that you will keep in mind that this nation is your people.