The proceeding verse tells us more:
“When wisdom entereth into thine heart, and knowledge is pleasant unto thy soul;” (Proverbs 2:10)
From the Bible, we can expect to be preserved by discretion. Discretion implies a level of understanding deep enough to “separate” between options combined with the liberty to act upon that judgement.
We can expect understanding to keep us. In other words, it will “maintain, to cause to continue,” but only if we choose to make it pleasant to our souls.
Right choices and safety. God’s Word changes lives.