Hi Wordsmith, first time we've met,(cordially held out my hand in friendship) Lol
None of us are able to judge the heart of Constantine, God will take care of that part, but we are to judge sin, and condemn it where we see it, and on the outside it appears he had an evil streak as well as a good one as is true with most people, but a ruler's sins are recorded for everyone to see, whereby ours go un-noticed by history.
To me these legal executions as you call them appear to be more vengeful then mechanical as most executions are, such as scalding his wife to death, or strangling someone, that points to a revengeful murder and a certain pleasure taken in the act.
If a man's life is 50% decent or good, and is 50% evil, and he dies, his life is looked at as an evil life, since the effects of his evil are remembered, more then hi acts of good.
If a man's life is 50% good, and 50% evil, and on his death bed, he repents and is converted, he is forgiven by God for all his past sins, but God does not then give him credit for those 50% good things he did with out God's Spirit in him, which with the bad thing's forgiven him, all that was left were the good things, therefore it is deemed he will be rewarded for his 50% good he did in the kingdom, and the 50% evil is no more.
WE will be judged on what we do after conversion, not before, and if he died immediately after conversion before he had time to make any changes in his life, then the only credit he will receive in heaven is that he repented, such as the thief on the cross, but he will receive no rewards, as others who spend their life bearing fruits.
His rewards may simply be that he attained eternal life, but he may have no other rewards, or be given any real responsibilities compared to the patient Christian who didn't have the opportunities that Constantine had to accomplish great things, but they multiplied their talents a 100 fold, so now we have a man who at one time was the most powerful ruler on earth, and in the kingdom he will have no rewards, meaning he may be under any one of us.
If he's under me, I'm sure going to let him know how he blew it. Lol JH