Anyone who wants the answer to this question should study the miracles in the Bible. Some people call almost anything good or amazing a miracle. Because God is who He is, everything He does is powerful, wonderful and good.
James 1:17, Every good and perfect gift is from above, coming down from the Father of the heavenly lights, who does not change like shifting shadows. However, in the Bible God does not call everything He does a miracle or a sign. Now let us think about God’s work through Jesus.
Many people of many different religions claim to do miracles like Jesus did. You can test these claims. Just compare them with the true miracles in the Bible. How and why. Are all the healings instantly successful? Do they heal every kind of illness, even the ones that doctors never can cure? Do they show the different kinds of complete power over nature that Jesus showed?
Agents of Satan are many miracle workers today. Satan does speak against God’s Word in many ways, he (Satan) sometimes tries to use miracles to lead people astray. Here are the miracles. See Matthew 7:21–23, Not everyone who says to me, Lord, Lord, will enter the Kingdom of heaven, but only he who does the will of my Father who is in heaven. Many will say to me on that day, Lord, Lord, did we not prophesy in your name and in your name drive out demons and perform many miracles? Then I will tell them plainly, I never knew you. Away from me, you evildoers! Also read Matthew 24:24, For false Christs and false prophets will appear and perform great signs and miracles to deceive even the elect – if that were possible. Read 2nd Thessalonians 2:9, The coming of the lawless one will be in accordance with the work of Satan displayed in all kinds of counterfeit miracles, signs and wonders. See Revelation 13:13, And he performed great and miraculous signs, even causing fire to come down from heaven to earth in full view of men. Also see Revelation 16:14, They are spirits of demons performing miraculous signs, and they go out to the kings of the whole world, to gather them for the battle on the great day of God Almighty. Read Revelation 19:20, But the beast was captured, and with him the false prophet who had performed the miraculous signs on his behalf. With these signs he had deluded those who had received the mark of the beast and worshiped his image. The two of them were thrown alive into the fiery lake of burning sulfur. That is why the Bible commands us to test those who claim to use great powers from God. See 1st John 4:1, Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world. Also see Revelation 2:2, I know your deeds, your hard work and your perseverance. I know that you cannot tolerate wicked men, that you have tested those who claim to be apostles but are not, and have found them false. Read 1st Thessalonians 5:21, Test everything. Hold on to the good.
Their teachings can easily be tested because God has already spoken clearly and fully through His Son. See Hebrews 1:1–2, In the past God spoke to our forefathers through the prophets at many times and in various ways, but in these last days He has spoken to us by His Son, whom He appointed heir of all things, and through whom He made the universe. Also see Hebrews 2:1, We must pay more careful attention, therefore, to what we have heard, so that we do not drift away. Read 2nd Peter 1:3, His divine power has given us everything we need for life and godliness through our knowledge of Him who called us by His own glory and goodness. Also see Jude 3 if you can. Their miracles can easily be tested because God has already given clear descriptions of His true miracles. Notice, become rich without education that leads to good work or hard labour that leads to riches is not a true miracle.
Think, for example, about healing. Sick people often get well. God usually works this healing through natural means that are slow. But when God healed through His Son Jesus, He always healed instantly, not slowly. He immediately healed every kind of illness, even sicknesses that no doctor on earth could ever heal. Acts 2:22, Men of Israel, listen to this : Jesus of Nazareth was a man accredited by God to you by miracles, wonders and signs, which God did among you through Him, as you yourselves know. Also read Acts 10:38, How God anointed Jesus of Nazareth with the Holy Spirit and power, and how He went around doing good and healing all who were under the power of the devil, because God was with Him.
Remember that the greatest sign and miracle from God to the human race was this: Jesus was crucified and died on a cross, was buried, but came back to life again by God’s power. All of biblical prophecy shows this truest miracle to anyone who has eyes to see.
God bless you.