God took Israel into the wilderness to teach them He was sufficient and to deliver them from the false things they were trusting in.
The serpents bit them and God made them look at the source of their trouble in order to be healed.
John 3:14 “And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up: that whosoever believeth in him should not perish, but have eternal life.”
 The source of mans problem is sin. God has provided our cure. Look to Jesus and live.
“For he hath made him to be sin for us, who knew no sin; that we might be made the righteousness of God in him.” II Corinthians 5:21
II Timothy 2:25,26 “In meekness instructing those that oppose themselves; if God peradventure will give them repentance to the acknowledging of the truth; and that they may recover themselves out of the snare of the devil, who are taken captive by him at his will.”