The signs have gradually ceased after the transition period from the OT to church age was over. The apostles could no longer heal.
1 Tim 5:23
Drink no longer water, but use a little wine for thy stomach's sake and thine often infirmities.
Phil 2:26-30
26 For he longed after you all, and was full of heaviness, because that ye had heard that he had been sick.
27 For indeed he was sick nigh unto death: but God had mercy on him; and not on him only, but on me also, lest I should have sorrow upon sorrow.
28 I sent him therefore the more carefully, that, when ye see him again, ye may rejoice, and that I may be the less sorrowful.
29 Receive him therefore in the Lord with all gladness; and hold such in reputation:
30 Because for the work of Christ he was nigh unto death, not regarding his life, to supply your lack of service toward me.
Signs are for the jews.
2 Cor 1:22-24
22 For the Jews require a sign, and the Greeks seek after wisdom:
23 But we preach Christ crucified, unto the Jews a stumblingblock, and unto the Greeks foolishness;
24 But unto them which are called, both Jews and Greeks, Christ the power of God, and the wisdom of God.
2 Cor 5:7
(For we shall walk by faith not by sight.)
Rom 10:17
17 So then faith cometh by hearing, and hearing by the word of God.
Matt 12:39
39 But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas:
Signs and wonders will be used by satan
Matt 24:24
24 For there shall arise false Christs, and false prophets, and shall shew great signs and wonders; insomuch that, if it were possible, they shall deceive the very elect.
2 Thes 2:9
9 Even him, whose coming is after the working of Satan with all power and signs and lying wonders,
Speaking in tongues (audible language) should be interpreted
1 Cor 14:9 ,13-14,27
9 So likewise ye, except ye utter by the tongue words easy to be understood, how shall it be known what is spoken? for ye shall speak into the air.
13 Wherefore let him that speaketh in an unknown tongue pray that he may interpret.
14 For if I pray in an unknown tongue, my spirit prayeth, but my understanding is unfruitful.
27 If any man speak in an unknown tongue, let it be by two, or at the most by three, and that by course; and let one interpret.
1 Cor 13:1
13 Though I speak with the tongues of men and of angels, and have not charity, I am become as sounding brass, or a tinkling cymbal.
Rev 14:6
6 And I saw another angel fly in the midst of heaven, having the everlasting gospel to preach unto them that dwell on the earth, and to every nation, and kindred, and tongue, and people,
Rev 16:5
5 And I heard the angel of the waters say, Thou art righteous, O Lord, which art, and wast, and shalt be, because thou hast judged thus.