Do you need proof before you will obey God? If so, then you have a problem with trust. This is called walking by the flesh (using your five senses and human reasoning) instead of walking by the spirit. In Matthew 16, Jesus teaches about the fourth and last enemy of believing – human reasoning.
The Pharisees also with the Sadducees came, and tempting desired him that he would shew them a sign from heaven.
The religious leaders came to tempt him looking for a sign. The devil is called the Tempter, so all tempting in the Bible is for evil motives.
2 He answered and said unto them, When it is evening, ye say, It will be fair weather: for the sky is red.
3 And in the morning, It will be foul weather to-day: for the sky is red and lowering. O ye hypocrites, ye can discern the face of the sky; but can ye not discern the signs of the times?
Sailors discern the weather by observing the sky. Yet, the Pharisees and Sadducees are not aware of what is written in the Bible.
4 A wicked and adulterous generation seeketh after a sign, and there shall no sign be given unto it, but the sign of the prophet Jonas. And he left them and departed.
Jesus did not have a high opinion of sign-seekers. The only sign that they needed was concerning Jonas. Matthew 12:40
For as Jonas was three days and three nights in the whale’s belly; so shall the Son of man be three days and three nights in the heart of the earth.
According to Romans 10:9-10, salvation requires us to confess Jesus as Lord and believe in our hearts that God raised him from the dead. He was raised after three days and three nights in the earth.
5 And when his disciples came to the other side, they had forgotten to take bread.
6 Then Jesus said unto them, Take heed and beware of the leaven of the Pharisees and of the Sadducees.
7 And they reasoned among themselves, saying, It is because we have taken no bread.
Jesus is using leaven figuratively and the disciples are taking it literally. Understanding Figures of Speech is vital to rightly divide the Bible. It determines error and truth.
8 Which when Jesus perceived, he said unto them, O ye of little faith, why reason ye among yourselves, because ye have brought no bread?
Jesus told them that they had little believing. I would not want Jesus to say that I had little believing. The problem was that they did not engage their brains and remember what they had seen and heard.
9 Do ye not yet understand, neither remember the five loaves of the five thousand and how many baskets ye took up?
10 Neither the seven loaves of the four thousand and how many baskets ye took up?
On two memorable occasions, they had seen miracles regarding insufficient bread.
11 How is it that ye do not understand that I spoke it not to you concerning bread, that ye should beware of the leaven of the Pharisees and of the Sadducees?
12 Then understood they how that he bade them not beware of the leaven of bread, but of the doctrine of the Pharisees and of the Sadducees.
Now they understood the figure, that just like a little leaven (yeast) will permeate a whole loaf of bread then religious doctrines will permeate and influence the whole Word of God. These religious doctrines are man’s thoughts, ways, and traditions.
Acts 17:11 is our instruction for discerning religious doctrine.
The Jews at Berea were of a nobler disposition than those in Thessalonica, for they very readily received the Message, and day after day searched the Scriptures to see whether it was as Paul stated.