Yes, faith [as per Heb 11:1], but meaning that we really make no assumptions or presumptions based on what we already believe. I believe that our whole connection with God consists of things held by faith and things which we know. The problem is that I also believe we do not know which ones are which. That is... which ones are really God's truth and which one we only believe are God's truth. The difference, as we see by the multitude of denominations based supposedly on the same Bible and the multitude of individual doctrinal differences even on such a relatively small forum as this one, is sometimes tremendous. How do we separate that which we believe falsely and that which is really God's take on it? I look first to this parable:
"When thou art bidden of any man to a wedding, sit not down in the highest room; lest a more honourable man than thou be bidden of him;
And he that bade thee and him come and say to thee, Give this man place; and thou begin with shame to take the lowest room
But when thou art bidden, go and sit down in the lowest room; that when he that bade thee cometh, he may say unto thee, Friend, go up higher: then shalt thou have worship in the presence of them that sit at meat with thee.
For whosoever exalteth himself shall be abased; and he that humbleth himself shall be exalted." Luke 14:8-11
How often should go to the "lowest room"? As often we are bidden by God to come! Humble ourselves down to the nothing we are in all of what we believe is our clear understanding... and then as appropriate and as He sees fit, He [God] will exalt us. He will give us back the things we set aside in taking the lowest place which were correct or replaced them with something better...He does the exalting... not us.
I do try to do this every day... and sometimes with God's help I may be changed for the better, better that is according to Him. Can we judge ourselves fairly in such a case?
Trouble with doing this? Also ask for help as per Matt 7:7-8. Also seek as per Matt 6:33... and so forth. You make the best use you can of what God has given you and will He not help you to improve?