Kyle, Thomas Watson in his exposition of the Shorter Catechism writes;

Some sins in themselves, and by reason of several aggravations, are more heinous in the sight of God than others.
'He that delivered me unto thee, hath the greater sin.'John 19:11 The Stoic philosophers held that all sins were equal; but this Scripture clearly holds forth that there is a gradual difference in sin; some are greater than others; some are 'mighty sins,' and crying sins.' Amos 5:12; Gen 18:21. Every sin has a voice to speak, but some sins cry. As some diseases are worse than others, and some poisons more venomous, so some sins are more heinous. 'Ye have done worse than your fathers, your sins have exceeded theirs.' Jer 16:12; Ezek 16:47. Some sins have a blacker aspect than others; to clip the king's coin is treason; but to strike his person is a higher degree of treason. A vain thought is a sin, but a blasphemous word is a greater sin. That some sins are greater than others appears, (1) Because there was difference in the offerings under the law; the sin offering was greater than the trespass offering. (2) Because some sins are not capable of pardon as others are, therefore they must needs be more heinous, as the blasphemy against the Holy Ghost. Matt 12:31. (3) Because some sins have a greater degree of punishment than others. 'Ye shall receive the greater damnation.' Matt 23:14. 'Shall not the Judge of all the earth do right?' God would not punish one more than another if his sin was not greater. It is true, 'all sins are equally heinous in respect of the object,' or the infinite God, against whom sin is committed, but, in another sense, all sins are not alike heinous; some sins have more bloody circumstances in them, which are like dye to the wool, to give it a deeper colour.

[1] Such sins are more heinous as are committed without any occasion offered; as when a man swears or is angry, and has no provocation. The less the occasion of sin, the greater is the sin itself.
[2] Such sins are more heinous that are committed presumptuously. Under the law there was no sacrifice for presumptous sins. Num 15:30.

Hope this is some help.
Brian.