Why did God give miraculous gifts?

¹And the LORD spake unto Moses, saying, ²See, I have called by name Bezaleel the son of Uri, the son of Hur, of the tribe of Judah: ³And I have filled him with the spirit of God, in wisdom, and in understanding, and in knowledge, and in all manner of workmanship, ⁴To devise cunning works, to work in gold, and in silver, and in brass, ⁵And in cutting of stones, to set them, and in carving of timber, to work in all manner of workmanship. ⁶And I, behold, I have given with him Aholiab, the son of Ahisamach, of the tribe of Dan: and in the hearts of all that are wise hearted I have put wisdom, that they may make all that I have commanded thee;

¹And when the day of Pentecost was fully come, they were all with one accord in one place. ²And suddenly there came a sound from heaven as of a rushing mighty wind, and it filled all the house where they were sitting. ³And there appeared unto them cloven tongues like as of fire, and it sat upon each of them. ⁴And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance. ⁵And there were dwelling at Jerusalem Jews, devout men, out of every nation under heaven. ⁶Now when this was noised abroad, the multitude came together, and were confounded, because that every man heard them speak in his own language. ⁷And they were all amazed and marvelled, saying one to another, Behold, are not all these which speak Galilæans? ⁸And how hear we every man in our own tongue, wherein we were born? ⁹Parthians, and Medes, and Elamites, and the dwellers in Mesopotamia, and in Judæa, and Cappadocia, in Pontus, and Asia, ¹⁰Phrygia, and Pamphylia, in Egypt, and in the parts of Libya about Cyrene, and strangers of Rome, Jews and proselytes, ¹¹Cretes and Arabians, we do hear them speak in our tongues the wonderful works of God.

¹⁵And he said unto them, Go ye into all the world, and preach the gospel to every creature. ¹⁶He that believeth and is baptized shall be saved; but he that believeth not shall be damned. ¹⁷And these signs shall follow them that believe; In my name shall they cast out devils; they shall speak with new tongues; ¹⁸They shall take up serpents; and if they drink any deadly thing, it shall not hurt them; they shall lay hands on the sick, and they shall recover. ¹⁹So then after the Lord had spoken unto them, he was received up into heaven, and sat on the right hand of God. ²⁰And they went forth, and preached every where, the Lord working with them, and confirming the word with signs following. Amen.

¹⁴Now when the apostles which were at Jerusalem heard that Samaria had received the word of God, they sent unto them Peter and John: ¹⁵Who, when they were come down, prayed for them, that they might receive the Holy Ghost: ¹⁶(For as yet he was fallen upon none of them: only they were baptized in the name of the Lord Jesus.) ¹⁷Then laid they their hands on them, and they received the Holy Ghost. ¹⁸And when Simon saw that through laying on of the apostles’ hands the Holy Ghost was given, he offered them money, ¹⁹Saying, Give me also this power, that on whomsoever I lay hands, he may receive the Holy Ghost.