If God is Holy, is killing gays, adulterers, murderers, Sabbath breakers also holy?

Atheistic confusion concerning the harshness of God’s Law and His holiness (an explanation): “…if God is holy, then it makes sense that everything he [He] commands is holy. Therefore, killing the gays, adulterers, apostates, Sabbath breakers and one's unruly Children must therefore must also be holy! So why do most modern Christians object?”

Christian response,

Premise: Everything that God commands is for good and holiness and righteousness concerning His purposes in Time and in Eternity.

God the Father is currently dealing with a rebellion, an unfathomable war, that was initiated in the Kingdom of God before the creation of Time (Isaiah 14; Ezekiel 28:11-17; 2 Timothy 1:9-10). In fact, it is this cosmic war, receiving formal declaration in Genesis 3:15, that is causation for the creation of matter, Time, the Universe, our complex genome. An integral part of God’s Plan to deal with the rebellion in the Kingdom, a rebellion that was extricated from the Kingdom and strategically placed within the Realm of Time and partially constrained by physics, is the setting-apart of a specific people group through whom God the Father would display His omnipotence and holiness and righteousness to the faithful angelic creation and all of human kind (Leviticus 20:26). Through the Patriarchy of Abraham, Isaac, Jacob and through the ministry and leadership of Moses, God the Father decreed that the children of Jacob (Israel) would be holy as God is Holy (Leviticus 19:2; Leviticus 20:7; Leviticus 20:26; Leviticus 21:8; 1 Peter 1:16). The holiness of Israel was essential as God the Father predestined this people group, specifically the Tribe of Judah, to introduce His Messiah into the Realm of Time; a Messiah that would destroy the works of the Devil (1 John 3:8b) and be a blessing to every family of the Earth (Genesis 12:3).

Again, the holiness and obedience of Israel was essential; therefore, God the Father provided the Hebrew Tribes with the Sinai Commandments and eventually the 613-Levitical Laws which were multifaceted in their purpose and function. The Law clearly articulated God’s standard of holiness and righteousness; the Law pointed the Hebrew Tribes to their need for Messiah as no sinful man (Romans 3:23) could keep the Law in perfection (Romans 3:20; Romans 10:5; Leviticus 18:5) which was necessary if righteousness was to be attained through the Law (James 2:10). God the Father incorporated extremely harsh penalties for crimes of moral turpitude that by their very nature manifest in dissension among the people i.e. murder, adultery, rebellion to one's parents, homosexuality (which directly attacked the Covenant of Marriage – the family unit essential for a sustainable society). Even the Sabbath Day, given specifically to the children of Israel, was to be kept Holy and observed as this observance kept the heart of the people focused on God and acted as a bulwark against compromise with the paganism that surrounded them and often times sought to seduce them. To clearly understand the Sabbath Day's necessity in the Covenant of Law, one must understand the differentiation between the allocated and peripheral work of the Holy Spirit in the Hebrew Scriptures and the indwelling work of the Spirit in the Covenant of Grace.

As I noted earlier, rebellion is the causation for our existence in Time and God would not tolerate rebellion and dissension among the people through whom Messiah was to manifest to the World. So yes, God's edicts concerning death for those who engaged in antisocial conduct that would thwart God’s Plan concerning Messiah and salvation to all of human kind through our Messiah are based in holiness and righteousness. God decreed that these moral crimes were of such veracity, destructiveness, seriousness in their potential for dissension among the people that He decreed a severe penalty to stymie their destructiveness; therefore, the death penalty for homosexuals, adultery, murder, disobedient children, rejection of the Sabbath, is directly in response to God’s holiness and righteousness and faithfulness as God loves both His angelic and human creation and desires that everyone who will trust in Him through His Messiah as Lord will be saved (John 3:16; 14:6) and through that salvation the works of the Devil are destroyed and the Kingdom’s holiness and purity assured forever (1 John 3:8b).

The faithful and studious Christian wholly concurs with God’s Law given specifically to the children of Israel and converts to Judaism during a specific and crucial dispensation (Covenant of Law) as the Law manifest to ensure the first-Advent of Messiah within the Realm of Time who would destroy the works of the Devil (1 John 3:8b) and offer salvation from death in sin and death in Hell to everyone who believes in Messiah Jesus as God and Mediator for sin (John 3:16-18). Jesus Christ, in His perfection, fulfilled the righteousness of the Law (Matthew 5:17) and offers mankind His own righteousness by grace (unmerited favor that cannot be earned) through faith (trusting-believing) in Jesus Christ as God and Mediator for sin as God the Father made Jesus to be sin for you and for me so that by believing in Jesus as our God and Savior, we can receive the perfection of Jesus imputed into and over our life and be declared “not guilty” of sin and thereby enjoy life and fellowship in Eternity with the Father (2 Corinthians 5:21). So yes, God's righteousness and holiness is displayed in the Law and even extends to the perceived harshness of the Law concerning violations of the moral code that thwarts God’s purposes and holiness in Time and in Eternity.