Genesis 1:19 And the evening and the morning were the fourth day.
See the Typology of Day Four in Prophetic Views
Numbers 7:30 On the fourth day Elizur the son of Shedeur, prince of the children of Reuben, did offer:
Numbers 29:23 And on the fourth day ten bullocks, two rams, and fourteen lambs of the first year without blemish:
Judges 19:5 And it came to pass on the fourth day, when they arose early in the morning, that he rose up to depart: and the damsel’s father said unto his son in law, Comfort thine heart with a morsel of bread, and afterward go your way.
2 Chronicles 20:26 And on the fourth day they assembled themselves in the valley of Berachah; for there they blessed the LORD: therefore the name of the same place was called, The valley of Berachah, unto this day.
Ezra 8:33 Now on the fourth day was the silver and the gold and the vessels weighed in the house of our God by the hand of Meremoth the son of Uriah the priest; and with him was Eleazar the son of Phinehas; and with them was Jozabad the son of Jeshua, and Noadiah the son of Binnui, Levites;
Zechariah 7:1 And it came to pass in the fourth year of king Darius, that the word of the LORD came unto Zechariah in the fourth day of the ninth month, even in Chisleu;
The 2 Chronicles passage tells of the stunning victory which Jehoshaphat won over a large enemy alliance, by sending the choir singing and worshiping the Lord in front of the Jewish army!
The Ezra passage relates how Ezra asked the returning exiles to fast for divine protection, as he was ashamed to ask the Persian King for protection which would be tantamount to expressing lack of faith in the armies of the Lord of Hosts. The Lord honored the returning exiles, and they arrived in Jerusalem safe, with considerable amount of gold and silver and vessels of copper intended for the rebuilding of the house of the Lord in Jerusalem.
The Zechariah passage is a word from the Lord through Zechariah warning the people that fasting was not pleasing to God if they failed to execute true judgment, and shew mercy and compassions every man to his brother, and instead continued to oppress the widow, the fatherless, the stranger, and the poor; and imagine evil against his brother in the heart.