And it shall come to pass in the last days, saith God, I will pour out of my Spirit upon all flesh: and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams (Acts 2:17).
And Jacob went out from Beersheba, and went toward Haran. And he lighted upon a certain place, and tarried there all night, because the sun was set; and he took of the stones of that place, and put them for his pillows, and lay down in that place to sleep. And he dreamed, and behold a ladder set up on the earth, and the top of it reached to heaven: and behold the angels of God ascending and descending on it. And, behold, the LORD stood above it, and said, I am the LORD God of Abraham thy father, and the God of Isaac: the land whereon thou liest, to thee will I give it, and to thy seed; And thy seed shall be as the dust of the earth, and thou shalt spread abroad to the west, and to the east, and to the north, and to the south: and in thee and in thy seed shall all the families of the earth be blessed. And, behold, I am with thee, and will keep thee in all places whither thou goest, and will bring thee again into this land; for I will not leave thee, until I have done that which I have spoken to thee of. And Jacob awaked out of his sleep, and he said, Surely the LORD is in this place; and I knew it not (Genesis 28:10-16).
Symbolic Actions-
The word which came to Jeremiah from the LORD, saying, Arise, and go down to the potter's house, and there I will cause thee to hear my words. Then I went down to the potter's house, and, behold, he wrought a work on the wheels. And the vessel that he made of clay was marred in the hand of the potter: so he made it again another vessel, as seemed good to the potter to make it. Then the word of the LORD came to me, saying, O house of Israel, cannot I do with you as this potter? saith the LORD. Behold, as the clay is in the potter's hand, so are ye in mine hand, O house of Israel. At what instant I shall speak concerning a nation, and concerning a kingdom, to pluck up, and to pull down, and to destroy it; If that nation, against whom I have pronounced, turn from their evil, I will repent of the evil that I thought to do unto them. And at what instant I shall speak concerning a nation, and concerning a kingdom, to build and to plant it; If it do evil in my sight, that it obey not my voice, then I will repent of the good, wherewith I said I would benefit them (Jeremiah 18:1-10).
Still Small Voice-
And he came thither unto a cave, and lodged there; and, behold, the word of the LORD came to him, and he said unto him, What doest thou here, Elijah? (1 Kings19:9).
Gentle Whisper-
And after the earthquake a fire; but the LORD was not in the fire: and after the fire a still small voice (1 Kings 19:12).
Miraculous Signs-
And the LORD said unto Moses, Rise up early in the morning, and stand before Pharaoh; lo, he cometh forth to the water; and say unto him, Thus saith the LORD, Let my people go, that they may serve me. Else, if thou wilt not let my people go, behold, I will send swarms of flies upon thee, and upon thy servants, and upon thy people, and into thy houses: and the houses of the Egyptians shall be full of swarms of flies, and also the ground whereon they are. And I will sever in that day the land of Goshen, in which my people dwell, that no swarms of flies shall be there; to the end thou mayest know that I am the LORD in the midst of the earth. And I will put a division between my people and thy people: to morrow shall this sign be. And the LORD did so; and there came a grievous swarm of flies into the house of Pharaoh, and into his servants' houses, and into all the land of Egypt: the land was corrupted by reason of the swarm of flies. And Pharaoh called for Moses and for Aaron, and said, Go ye, sacrifice to your God in the land (Exodus 8:20-25).
Creation And Nature-
For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who hold the truth in unrighteousness; Because that which may be known of God is manifest in them; for God hath shewed it unto them. For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse (Rom 1:18-20).
To the chief Musician, A Psalm of David. The heavens declare the glory of God; and the firmament sheweth his handywork (Psalms 19:1).
Prophets-
God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets (Heb 1:1).
Other People-
For to one is given by the Spirit the word of wisdom; to another the word of knowledge by the same Spirit; To another faith by the same Spirit; to another the gifts of healing by the same Spirit; To another the working of miracles; to another prophecy; to another discerning of spirits; to another divers kinds of tongues; to another the interpretation of tongues (1 Corinthians 12:8-10).
If any man speak, let him speak as the oracles of God; if any man minister, let him do it as of the ability which God giveth: that God in all things may be glorified through Jesus Christ, to whom be praise and dominion for ever and ever. Amen (1 Peter 4:11).
Holy Spirit-
He that hath an ear, let him hear what the Spirit saith unto the churches; To him that overcometh will I give to eat of the tree of life, which is in the midst of the paradise of God (Rev 2:7).
For it is not ye that speak, but the Spirit of your Father which speaketh in you (Mat 10:20).
But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you (John 14:26).
It is the spirit that quickeneth; the flesh profiteth nothing: the words that I speak unto you, they are [the words of the Holy] spirit, and they are life (John 6:63).
Then the [Holy] Spirit said unto Philip, Go near, and join thyself to this chariot (Acts 8:29).
Scripture-
All scripture is given by inspiration of God, andis profitable for doctrine, for reproof, for correction, for instruction in righteousness: That the man of God may be perfect, throughly furnished unto all good works (2 Timothy 3:16-17).
His Son, Jesus Christ-
God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets, Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds (Hebrews 1:1-2).
Jesus answered them, I told you, and ye believed not: the works that I do in my Father's name, they bear witness of me. But ye believe not, because ye are not of my sheep, as I said unto you. My sheep hear my voice, and I know them, and they follow me (John 10:25-27).
And as he journeyed, he came near Damascus: and suddenly there shined round about him a light from heaven: And he fell to the earth, and heard a voice saying unto him, Saul, Saul, why persecutest thou me? And he said, Who art thou, Lord? And the Lord said, I am Jesus whom thou persecutest: it is hard for thee to kick against the pricks. And he trembling and astonished said, Lord, what wilt thou have me to do? And the Lord said unto him, Arise, and go into the city, and it shall be told thee what thou must do. And the men which journeyed with him stood speechless, hearing a voice, but seeing no man(Acts 9:3-7).
Audible Voice-
And they heard the voice of the LORD God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the LORD God amongst the trees of the garden (Genesis 3:8).
Signs-
And Gideon said unto God, If thou wilt save Israel by mine hand, as thou hast said, Behold, I will put a fleece of wool in the floor; and if the dew be on the fleece only, and it be dry upon all the earth beside, then shall I know that thou wilt save Israel by mine hand, as thou hast said. And it was so: for he rose up early on the morrow, and thrust the fleece together, and wringed the dew out of the fleece, a bowl full of water. And Gideon said unto God, Let not thine anger be hot against me, and I will speak but this once: let me prove, I pray thee, but this once with the fleece; let it now be dry only upon the fleece, and upon all the ground let there be dew. And God did so that night: for it was dry upon the fleece only, and there was dew on all the ground (Judges 6:36-40).
And when the people were gathered thick together, he began to say, This is an evil generation: they seek a sign; and there shall no sign be given it, but the sign of Jonas the prophet. For as Jonas was a sign unto the Ninevites, so shall also the Son of man be to this generation (Luke 11:29-30).
Conscience-
And Paul, earnestly beholding the council, said, Men and brethren, I have lived in all good conscience before God until this day (Act 23:1).
I say the truth in Christ, I lie not, my conscience also bearing me witness in the Holy Ghost (Romans 9:1).
Holding the mystery of the faith in a pure conscience (1 Timothy 3:9).
Donkey-
And the LORD opened the mouth of the ass, and she said unto Balaam, What have I done unto thee, that thou hast smitten me these three times? (Numbers 22:28).
Lastly, God may also speak to us in some novel way of His own choosing and for His own Purposes-