Psalms 1:1-2 - "Blessed is the man who does not walk in the counsel of the wicked or stand in the way of sinners or sit in the seat of mockers. But his delight is in the law of the Lord and on law he meditates day and night."
I just wanted you guys to read the whole passage. I am going to split these passages up into two parts.
Psalms 1:1 - "Blessed is the man who does not walk in the counsel of the wicked or stand in the way of sinners or sit in the seat of mockers."
Now this passage means that godly people should not do what ungodly people do. Now think about it. People who live in ungodly ways can influence you or give you "peer pressure". Being around ungodly people is not bad, in fact it is what we're called to do. But letting them influence how you live with their worldly views is wrong. Now, on the other hand, if you do walk around with godly people, they will influence you to make the right choices and remind you of scriptures when you have a problem.
Psalms 1:2 - But his delight is in the law of the Lord and on the law he meditates day and night."
This is a really important statement. If we are godly, we should be happy about the "law of the Lord". What do you think the "law of the Lord" is? It is the Bible. We should be joyful about what is in the Bible. The next part, "...and on the law he meditates day and night". Meditating day and night is basically thinking about the word and reading about the word every single second of your life. Now that's basically impossible, but the point is, is that thinking about the Bible (and what's in it, of course!) as often as you can, is meditating. So delighting and meditating in the Bible means that we should be joyful about the Bible and what's in it and be thinking about the Bible for as much as we can.
So, the two passages mean, we should not let ungodly people influence us negatively, but instead think about and read the Bible as much as we can.