Why do miracles that happened during biblical times no longer happen today?
Miracles in the Bible served two purposes. One was to show that the person performing the miracle was sent by God. “And Moses answered and said, But, behold, they will not believe me, nor hearken unto my voice: for they will say, The LORD hath not appeared unto thee. And the LORD said unto him, What is that in thine hand? And he said, A rod. And he said, Cast it on the ground. And he cast it on the ground, and it became a serpent; and Moses fled from before it. And the LORD said unto Moses, Put forth thine hand, and take it by the tail. And he put forth his hand, and caught it, and it became a rod in his hand: That they may believe that the LORD God of their fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath appeared unto thee.” (Exodus 4:1-5) “If I do not the works of my Father, believe me not. But if I do, though ye believe not me, believe the works: that ye may know, and believe, that the Father is in me, and I in him.” (John 10:37-38)
The second, related, reason was to create faith in those seeing the miracles. “And many other signs truly did Jesus in the presence of his disciples, which are not written in this book: But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name.” (John 20:30-31)
There are a few exceptions, but generally speaking most miracles were concentrated in three periods of the Bible. One was the exodus and the giving of the Law of Moses. A second period was the time of the prophets Elijah and Elishah, during Israel’s worst departure from God. The third was the life of Jesus and the beginning of the church. That the miracles would be primarily at these times makes sense considering the reasons for miracles given above.
We no longer have a reason for miracles. We have the completed word of God in the Bible. The miracles are written therein. If we are not going to believe reliable witnesses to the miracles, we would not believe the miracles themselves. Since God has already revealed his will to all men there is no reason for him to establish a new revelation to man. Therefore there is no reason for us to have miracles today.