Answer:
Before Constantine, Christian art depicted God´s altar in a naturalistic perspective as the dominant theme. Whilst the Constantine´s reforms helped Christianity to expand its influence and settle as the main religion of the Empire, the theme of Christian art underwent a progressive transformation.
Until IV century, the Christian imagery had been struggling with the internal disputes of the different Christian groups. Issue like the Trinity´s divinity were resolved until the First Council of Nicaea and as consequence of this the religious practices and the imagery projected a new stage of unity and domain of Christian Church.
Step-by-step explanation: