Proverbs 29:18a (KJV): Where there is no vision, the people perish ...
The word 'vision' here is pronounced 'khaw-zone' in Hebrew, which comes from the word 'khaw-zaw', meaning 'to gaze at, to perceive (mentally), to see, to behold, to have a vision of'.
In 2 Corinthians 12:1, Paul wrote, "It is doubtless not profitable for me to boast, (but) I will come to visions and revelations of the Lord." In Acts 2:17, Peter quoted Joel 2:28, saying "And it shall come to pass in the last days, says God, that I will pour out of My Spirit on all flesh; your sons and your daughters shall prophesy, your young men shall see visions, your old men shall dream dreams." Praise God, in our days (i.e. in the New Covenant), God's Spirit is being poured out on everyone who believes, and not just a selected few! It also means every believer can have dreams and see visions from the Lord! What you need is just to be open to such!
There are many ways God can communicate with you (e.g. through inner witness, still small voice, prophecy, dreams, visions, etc), and He still is in the 'business' of communicating with His beloved today. Of course, one very common way in these 'last days' is through 'seeing visions'. Like dreams, visions from the Lord are never pre-meditated beforehand, and definitely not as a result of watching too much television! Instead, it is a sovereign overtaking from the Lord. When one sees a vision from the Lord, it (be it a 'picture' or 'word/words') supersedes (i.e. take the place of) whatever one sees in the physical realm with his naked eye.
"What are the differences between 'dreams' and 'visions'?"
Basically, 'dreams' are given when one is sleeping, whereas 'visions' are given when one is not sleeping. Another difference is 'dreams' are like a 'drama show', whereas 'visions' are like a 'slide (or static) show'.
Unlike 'dreams', 'visions' generally concern one's calling, ministry, or plans of God. In other words, 'visions' normally concern God's kingdom, whereas 'dreams' may cover a much wider scope, including one's personal situation or circumstances.
'Visions' are also more likely a 'command' from the Lord, while 'dreams' are about a 'solution' from the Lord. However, both 'visions' and 'dreams' need one's spiritual understanding in interpreting it.
'Visions' serve to tell us more about 'what to do' (i.e. the knowledge on what to do), while 'dreams' seem to tell us more about 'how to do' (i.e. the wisdom on how to go about doing it).
This probably explains why the Bible says 'young men see visions', and 'old men dream dreams'. It is a known fact that younger men tend to seek God more on 'what to do' in life (or what they are called for in life, i.e their identity/purpose in life), but as they grow older, and as they grow in wisdom, they would then tend to seek God more on 'how to go about doing it'!
Note: Of course, it also doesn't mean young men can't dream 'dreams', and old men can't see 'visions'! Let's understand Joel 2:28 in the right context, i.e. according to its functions.
However, having written all the differences above, I would also conclude that 'visions' and 'dreams' may sometimes overlap each other in functions as well. One cannot distinctly separate these two like one separates night and day.
Types of vision found in the Bible:
1. Open visions (or 'visions in the heavenly realm'), e.g. Genesis 15:1, Ezekiel 1:1-3, Isaiah 6:1.
2. Trance visions (when one is in semi-conscious state), e.g. Acts 10:9-11.
3. Prophetic visions (can sometimes be symbolic pictures to be interpreted), e.g. Isaiah 2:1.
Purposes of vision found in the Bible:
1. Revealing God's plan, e.g. Isaiah 2:1-4.
2. Calling into ministry/vocation, e.g. Isaiah 6:1-8.
3. God making covenant with His people, e.g. Genesis 15:1-18.
4. Confirming a ministry calling, e.g. Acts 9:10-18.
5. Confirming an open door from the Lord, e.g. Acts 10:9-48, Acts 16:6-10.
How to handle visions?
1. Record it down, act on it, and make it known (if the Lord says so), e.g. Habakkuk 2:2-3.
2. Conceal it until the time is right to release/declare it, e.g. Matthew 17:1-9.
