John 3:9

How can these things be? - Our Lord had very plainly told him how these things could be, and illustrated the new birth by one of the most proper similes that could be chosen; but so intent was this great man an making every thing submit to the testimony of his senses that he appears unwilling to believe any thing, unless he can comprehend it. This is the case with many - they profess to believe because they comprehend; but they are impostors who speak thus: there is not a man in the universe that can fully comprehend one operation, either of God or his instrument nature; and yet they must believe, and do believe, though they never did nor ever can fully comprehend, or account for, the objects of their faith.

How can these things be? - Nicodemus was still unwilling to admit the doctrine unless he understood it; and we have here an instance of a man of rank stumbling at one of the plainest doctrines of religion, and unwilling to admit a truth because he could not understand "how" it could be, when he daily admitted the truth of facts in other things which he could as little comprehend. And we may learn:

1. that people will often admit facts on other subjects, and be greatly perplexed by similar facts in religion.

2. that no small part of people's difficulties are because they cannot understand how or why a thing is.

3. that people of rank and learning are as likely to be perplexed by these things as those in the obscurest and humblest walks of life.

4. that this is one reason why such men, particularly, so often reject the truths of the gospel.

5. that this is a very unwise treatment of truth, and a way which they do not apply to other things.

If the wind cools and refreshes me in summer if it prostrates the oak or lashes the sea into foam - if it destroys my house or my grain, it matters little how it does this; and so of the Spirit. If it renews my heart, humbles my pride, subdues my sin, and comforts my soul, it is a matter of little importance how it does all this. Sufficient for me is it to know that it is done, and to taste the blessings which flow from the renewing. and sanctifying grace of God.