Are all transgressions of the law equally heinous?

Answer

Some sins in themselves, and by reason of several aggravations, are more heinous in the sight of God than others (; ; ).

Read the 3 proof texts (KJV)

Ezekiel 8:6,13,15: ⁶He said furthermore unto me, Son of man, seest thou what they do? [even] the great abominations that the house of Israel committeth here, that I should go far off from my sanctuary? but turn thee yet again, [and] thou shalt see greater abominations. ¹³He said also unto me, Turn thee yet again, [and] thou shalt see greater abominations that they do. ¹⁵Then said he unto me, Hast thou seen [this], O son of man? turn thee yet again, [and] thou shalt see greater abominations than these.
1 John 5:16: If any man see his brother sin a sin [which is] not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it.
Psalm 78:17,32,56: ¹⁷And they sinned yet more against him by provoking the most High in the wilderness. ³²For all this they sinned still, and believed not for his wondrous works. ⁵⁶Yet they tempted and provoked the most high God, and kept not his testimonies: