Under the old covenant, the primary mark of an Israelite was circumcision. Anyone who was not circumcised was to be cut off from God's people, for he had broken the Divine covenant (Gen.17:14). In the new covenant, the spiritual meaning of circumcision is explained as "having no confidence in ourselves" (Phil.3:3). It is the one who has no confidence in himself whom God upholds and whom God anoints continuously with His Spirit. There is a prophecy concerning Jesus that states, "Behold My Servant Whom I uphold....I have put My Spirit upon Him" (Isa.42:1; see Matt.12:18) The anointing of the Holy Spirit is the prime essential for being a new covenant servant of God. And we see in this verse that God gives that anointing to those who are upheld by Him - that is, to those who are helplessly dependent on Him. Faith in God cannot be exercised until we have become weak in ourselves. Otherwise our faith will be in the arm of flesh - which could be either our own cleverness, ability and money, or the resources of other people whom we know and whom we can depend on. Let me illustrate: If a rich brother and a poor brother are both faced with a sudden financial need, who would have to trust in God more? Obviously the poor brother. The rich man has enough money. So he does not need to pray. But the poor brother, if he has faith, will cry out to God, and He will not be disappointed. It is when we don't have human resources to fall back on that we learn to live by faith. Even many so-called "full-time workers", who claim to be "living by faith", have fairly reliable human resources that they can depend on. They have brothers who can be depended on to send them money every month - just in case God lets them down!!
"Faith comes by hearing" (Rom.10:17). It is when we hear what God says that faith is born in our hearts. God speaks to us through the Scriptures and also through His Spirit. So, if we don't listen to God, we won't have faith. Our spiritual antennas must be attuned to listen to God the whole day, no matter what we are doing. To listen to God ALWAYS is one of the most important requirements fora servant of God. Jesus lived every day listening to, and obeying the promptings of the Holy Spirit (See Isa.50:4). That proved that He had no confidence in Himself and knew that only the Father could show Him what things had eternal value and what things didn't. We waste a lot of time doing things that have no eternal value, because we are in too much of a hurry to have time to listen to God. God wants to teach us how to live by faith in Him. Four times the Bible says that "the righteous shall live by faith". That does not refer to full-time workers, but to all believers. And so God arranges our circumstances such that we are compelled to turn to Him again and again for guidance. And if we are seeking for God's best, He will gradually take away the human props that we have depended on for so long, and bring us to the place where we trust Him alone for all our needs - whether those needs be financial or physical or whatever.
In 2 Chronicles 16:12 , we read that King Asa of Judah was sick. When a king is sick, he can afford to get the best physicians to treat him. Yet Asa died. Why? Because "even when his disease was severe, he did not seek the Lord, but depended on the doctors" (v.12). Now if a poor man in Israel had been sick, he would have had to seek the Lord, and the Lord could have healed him. It is when we are weak and our human resources are limited that we seek the Lord. Faith is such an important factor in the Christian life that we are told that "without faith, it is impossible to please God" (Heb.11:6). That means even if we live in purity and goodness, and never backbite or gossip or cheat or tell lies, and even if we give all our money for God's work, if we don't live by faith (in helpless dependence on God and with no confidence in ourselves), we still won't please Him. As servants of the new covenant, it is faith that we are impart to others in the church - not just Bible-knowledge. We have to teach them from our own experience how to trust the Lord in all situations.