My mother always used to tell me: Blessing comes when you keep a low profile. The Gemara in Taanis (8b) indeed teaches just that: Ain HaBracha Metzuyah Elah BeDavar HaSamui Bin HaAyin, Blessing happens only with things that are hidden from the eye.
If you have a great job and can take vacations, do not talk about them. All it is going to do is cause an ayin hara and create jealousy, which is almost sure to cause the eventual loss of the blessing.
If you merit having a livelihood, especially in these difficult days, do not talk about it. If something good happens in your life, there is only one person that you should tell it to who is guaranteed to be happy for you: your mother. No one else. Not your brother-in-law. Not your sister-in-law. No one!
I have another secret for you: If you have a beautiful home, do not make a lavish chanukas habayis. Not in today’s times. All it will do is cause people to say, “Where’d you get those curtains? Where’d you get that beautiful sink? Where’d you get the towels? Why don’t I have it?” [I]t will lead to jealousy and, chas v’shalom, ayin hara[.]
If you have anything that is going well for yourself in your life, keep quiet. Follow the advice of Chazal (and the advice of my mother): Keep a low profile.
Excerpt from “Perspectives of the Maggid .”
Followup: In Maseches Sanhedrin 14a it talks about R’ Zeira avoiding Semicha, though it was a great honor. His reasoning was based on a statement by Rabbi Elazar urging one to keep a low profile in order to survive. It was only when he heard another statement of this Sage that no one achieves greatness unless all of his sins are forgiven that he finally sought ordination. (source: http://ohr.edu/4200 )