The curtain rent in two means a couple things. 1 Kings 11:29-31, ahijah rips a new garment into 12 pieces and gives 10 to Jeroboam to signify 10 tribes would be ripped away from Solomon for idolatry and apostasy. So the rip of fabric signified a rip apart in relationship with god. So, the rip of the Holy curtain signified the relationship between god and Israel was now severed because they wanted his son killed and succeeded.  Also, since the Holy and Most Holy compartment of the temple (and earlier tabernacle) signified heaven itself, it means that the membrane between our world and heaven was now open (kinda like a hymen exists until a woman is no longer a virgin). Jesus was the first man to enter heaven and he broke the seal (John 3:13). Now more people would be allowed in after him, starting with his apostles.