I have been reading from past posts and write here my contributions to three of them. This is only what I think and what I was taught, conceding the fact that I might be wrong.
Baptism:
Both formulas are from the Bible
"Go ye therefore, and make disciples of all the nations, baptizing them into the name of the Father and of the Son and of the Holy Spirit" (Matthew 28:19) vs.
“Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins” (Acts 2:38)
[Sorry for the quotes from different translations of the Bible, I google them quickly.]
The first one has been the official formula from the beginning of the Church. The second one means "by the authority of Jesus," assuming the first formula is to be used. Yet, the latter has been taken out of context by different groups at different times for different reasons. Also, although it is not a valid argument, the first one are Jesus' words; the second one are Peter's. Who do we believe?
"God helps those who help themselves"
MisticCat explained it pretty well, so I won't repeat what has been said. I'll add that this is very dangerous phrase.
First, God is not limited by anything, including men's unwillingnes to help himself.
Second, I've actually heard people, in the same line of thought, quoting Paul when he says that those who don't work, don't eat. This is said in a very specific context and need not be taken out of it.
Finally, let's look at what it is being said behind the words: "Since God help those who help themselves, if you are in a hole, it means you are not helping yourself." There goes any help to Africa, any help to those in need anywhere in the world. "If they had helped themselves, God would help them."
Since the phrase is used as an excuse against helping others that may look lazy, I add my opinion, without being accused of being naive and always taking the much needed precautions so that it doesn't happen, a Christian should always prefer to be disappointed by trusting (even though some undeserving individuals might take advantage) than be surprised by doubting (and so doubting others worthy of such trust). The same can be apply to the help we provide. Some might abuse, most won't. Paraphrasing an Ignatian thought: I did not start helping others so that they may abuse of me, neither will I stop helping others because of it.
Creeds
The Niceno-Constantinopolitan creed was written to answer the heresies as they arose (Arianism > Jesus is not God) (Monophysitism > Jesus has only one nature and that is the Divine), etc. It was first stated at the Nicaea Council, and later confirmed at the Constantinopolitan Council, in order to clarify the misunderstandings which gave place to the heresies. The Apostle's Creed, probably older although its oldest written account is dated much later than the Niceno, states what Christians believed, probably taken phrases from the Bible, but allowing for the misunderstandings from which the heresies were born.
Now, I've always wondered why the Apostle's creed mentions "the communion of Saints" while the Niceno-Constantinopolitan doesn't. I know that the latter include it implicitly, but still.