"The Lord is with Joesph" means...
1. Joseph experienced God's presence. The Lord let him know that even though Joseph had been stripped of everything God was with him.
2. Providence (God is making things happen that wouldn't otherwise). God's goal is to have Joseph come into Pharaoh's presence.
3. Prosperity (success in whatever he did). Even Potiphar could see this. Potiphar and the prison warden recognized Joseph was naturally and supernaturally gifted in leadership, management, and administration. His father may have seen this and it may have been a factor in keeping Joseph out of the field. Potiphar also noted he's a hard worker, has good work ethic, and is trustworthy. Joseph respects, honours, and is loyal to leaders. He has a positive attitude towards adversity and seems to be pleasant to be around with a positive outlook. He is a man of moral convictions (integrity).
There are some dangers of success:
Idolatry (success can become a "god" and am obsession. You can be successful and not know God. Joseph shows that he was willing to lose "success" in order to remain faithful to God.)
Pride/arrogance (to counter this think: what is it that I have that didn't come from the Lord?)
Envy & flattery (you can displace people when you become successful. Flattery can go to your head).
Illusion of permanence/security (no guarantee in earthly power. Our security is in Christ who promises to never forsake us).
It brings temptations (if your character isn't mature enough to ground you in the Lord).
Joseph's success was about making others successful. God made him a blessing to noted.