Believing the Gospel as only Christ defines it is the act of obedience towards God. Christ commands us to believe and Faith is obedience to that commandment.
2Th 1:8 In flaming fire taking vengeance on them that know not God, and that obey not the gospel of our Lord Jesus Christ:
Moreover the word of the LORD came unto me, saying, Son of man, when the house of Israel dwelt in their own land, they defiled it by their own way and by their doings: their way was before me as the uncleanness of a removed woman. Wherefore I poured my fury upon them for the blood that they had shed upon the land, and for their idols wherewith they had polluted it: And I scattered them among the heathen, and they were dispersed through the countries: according to their way and according to their doings I judged them. And when they entered unto the heathen, whither they went, they profaned my holy name, when they said to them, These are the people of the LORD, and are gone forth out of his land. But I had pity for mine holy name, which the house of Israel had profaned among the heathen, whither they went. Therefore say unto the house of Israel, Thus saith the Lord GOD; I do not this for your sakes, O house of Israel, but for mine holy name's sake, which ye have profaned among the heathen, whither ye went. And I will sanctify my great name, which was profaned among the heathen, which ye have profaned in the midst of them; and the heathen shall know that I am the LORD, saith the Lord GOD, when I shall be sanctified in you before their eyes. For I will take you from among the heathen, and gather you out of all countries, and will bring you into your own land. Then will I sprinkle clean water upon you, and ye shall be clean: from all your filthiness, and from all your idols, will I cleanse you. A new heart also will I give you, and a new spirit will I put within you: and I will take away the stony heart out of your flesh, and I will give you an heart of flesh. And I will put my spirit within you, and cause you to walk in my statutes, and ye shall keep my judgments, and do them. And ye shall dwell in the land that I gave to your fathers; and ye shall be my people, and I will be your God. I will also save you from all your uncleannesses: and I will call for the corn, and will increase it, and lay no famine upon you. And I will multiply the fruit of the tree, and the increase of the field, that ye shall receive no more reproach of famine among the heathen. Then shall ye remember your own evil ways, and your doings that were not good, and shall lothe yourselves in your own sight for your iniquities and for your abominations. Not for your sakes do I this, saith the Lord GOD, be it known unto you: be ashamed and confounded for your own ways, O house of Israel. - Ezekiel 36:16-32
Repentance is a fruit of God's saving love.
Amen. John.6:28-29