Exodus 23:14
"Three times thou shalt keep a feast unto me in the year."
Cross References (ranked by relevance)
Three times in a year shall all thy males appear before the LORD thy God in the place which he shall choose; in the feast of unleavened bread, and in the feast of weeks, and in the feast of tabernacles: and they shall not appear before the LORD empty:
Even unto the morrow after the seventh sabbath shall ye number fifty days; and ye shall offer a new meat offering unto the LORD.
In the fourteenth day of the first month at even is the LORD’s passover.
Three times in the year all thy males shall appear before the LORD God.
Speak unto the children of Israel, saying, The fifteenth day of this seventh month shall be the feast of tabernacles for seven days unto the LORD.