Love is the greatest commandment...but not the only command.
For example:
Acts 15:28 For the holy spirit and we ourselves have favored adding no further burden to YOU, except these necessary things, 29 to keep abstaining from things sacrificed to idols and from blood and from things strangled and from fornication
1 Corinthians 10:14 Therefore, my beloved ones, flee from idolatry
1Cor 6:9 What! Do YOU not know that unrighteous persons will not inherit Gods kingdom? Do not be misled. Neither fornicators, nor idolaters, nor adulterers, nor men kept for unnatural purposes, nor men who lie with men, 10 nor thieves, nor greedy persons, nor drunkards, nor revilers, nor extortioners will inherit Gods kingdom. 11 And yet that is what some of YOU were. But YOU have been washed clean, but YOU have been sanctified, but YOU have been declared righteous in the name of our Lord Jesus Christ and with the spirit of our God
Colossians 3:5 Deaden, therefore, YOUR body members that are upon the earth as respects fornication, uncleanness, sexual appetite, hurtful desire, and covetousness, which is idolatry. 6 On account of those things the wrath of God is coming. 7 In those very things YOU, too, once walked when YOU used to live in them. 8 But now really put them all away from YOU, wrath, anger, badness, abusive speech, and obscene talk out of YOUR mouth. 9 Do not be lying to one another. Strip off the old personality with its practices,
There are plenty of laws that the christian congregation held onto... but the only parts of the mosaic law that they did not believe applied was the dietry restrictions or observances of festivals, the priesthood, the sacrificial system & ritual cleaning...none of Gods servants who lived before the mosaic law observed these things so they were not morally binding on mankind to observe. They were specifically for Isreal.