Acts 2:41

41. The multitude, who had been so pierced to the heart by Peter's discourse, as to cry out, "Brethren, what shall we do?" were happily surprised to find the terms of pardon so easy. (41) " Then they gladly received his word, and were immersed; and the same day there were added about three thousand souls. " The pronoun they identifies the parties immersed with those who had cried out, What shall we do? It shows that they promptly complied with the command which Peter had given them. The word which they gladly received can not be the main part of Peter's speech, for this had pierced them to the heart; but it is the word of his answer, which gave their feelings great relief by opening to them so easy a method of escape from the doom which they dreaded, and which they so richly deserved.

Times without number the objection has been urged, and as often refuted, that three thousand men could not have been immersed in so short a time, and with the inadequate supply of water afforded in Jerusalem. As to the quantity of available water, Dr. J. T. Barclay, in his work entitled "The City of the Great King," written during a residence of three years and a half in Jerusalem, as a missionary, shows that Jerusalem was anciently better supplied with water than any other city known to history not permeated by living streams. Even to the present day, though most of the public reservoirs are now dry, such as the supposed pool of Bethesda, 365 feet long by 131 in breadth, and the lower pool of Gihon, 600 long by 260 in breadth, there are still in existence bodies of water, such as the pool of Siloam, and the pool of Hezekiah, affording most ample facilities for immersing any number of persons.

As to the want of time for the immersion of so many, any one who will make the mathematical calculation, without which it is folly to offer the objection, will find that there was the greatest abundance of time. Allowing that Peter's speech commenced at nine o'clock, as he himself states in verse 15, and that the exercises at the temple closed at noon, we have left six hours till sunset. To immerse sixty men in an hour would be very deliberate work for one administrator. But there were twelve administrators, hence, each hour there were not less than seven hundred and twenty persons immersed. At this rate, in less than four and one-fourth hours the whole multitude would be immersed, leaving the sun nearly two hours high when the last candidate emerged from the water. In view of this simple calculation, which a child could make, it is truly astonishing that so many grave critics and preachers should urge this objection. It strikingly illustrates the blinding effects of partisan zeal.

Now that the three thousand are added to the Church, we may glance back over the history of the day, and learn upon what preparation they were received to the fellowship of the disciples. To accomplish this, we must first consider their state of mind before Peter spoke to them, and then observe the changes through which they passed. Being Jews, then, they were already believers in the true God, and in the inspiration of the Old Testament scriptures. Luke declares, also, that they were "devout men." They were, however, unbelievers in reference to Jesus Christ, and they were guilty of participating in his crucifixion. At the moment that Peter arose to speak, they were full of amazement at witnessing the immersion of the twelve in the Holy Spirit, but their religious character remained unchanged. Peter speaks; and, at the conclusion of his argument, there is an evident change in their convictions. But they believe now nothing additional to what they did at first, except what Peter has proved to them. He has attempted to prove, however, only two propositions: first, That he and the eleven were inspired; second, That Jesus of Nazareth was now both Lord and Christ. The first, moreover, was established only as a means of proving the second. Several other subordinate facts were also proved for the same purpose, so that the whole speech is properly resolved into an attempt to prove the single proposition with which it concludes, that "God has made that same Jesus, whom you have crucified, both Lord and Christ." This, then, is what the three thousand believed, and this is all that distinguished their faith when immersed, from what it was before they heard the gospel from Peter's lips.

But another change had occurred within them. Under the influence of their new faith, they were pierced to the heart with a sense of guilt. This is the "godly sorrow" which "works repentance," and it prepared them to promptly obey Peter's command, "Repent, and be immersed." They repented, and were immersed. Their conversion, therefore, consisted in believing that Jesus is the Christ, repenting of their sins, and being immersed. This entitled them to membership in the Church, and so it does every human being who does likewise.