Then the LORD opened Balaam’s eyes, so that he saw the angel of the LORD standing on the road with sword drawn; and he knelt and bowed down to the ground. - Numbers 22: 31
This verse is from the Scripture passage which is the inspiration for the name of this blog.
Balaam was obviously blind to the presence of the angel of the Lord. He was only focused on the donkey. More accurately, he was focused on the donkey not doing what he wanted her to do. He was thinking about himself and what he wanted to do, where he wanted to go.
Scripture tells us that God communicated with Balaam before this donkey business, and that Balaam had obeyed God in the past. But now he was doing his own thing. Blind.
It turns out that Balaam is no hero. He instructs Balak how to get the Israelites to curse themselves through vice. Balaam is offered as an example of a false prophet in 2nd Peter and Jude, and even gets a mention (negatively) in Revelation.
It's not only vice and avarice that are "stumbling blocks" and contributing to our blindness.
Regardless of the state of our relationship with God, when we begin focusing on ourselves and see the circumstances in our lives only as they affect us, we become blind to what is important. Even worse, we become blind to what God might be trying to work in and through us.