The picture on men's swimming scholarships is not very pretty these days. Title IX and men's football programs serve to limit the scholarships available. There are three associations that provide men's swimming scholarships--NCAA Div. 1 and 2 and NAIA. Here are the websites that provide the schools in NCAA Div. 2 and NAIA:
NCAA Div. 2: NCAA Division II
In NCAA Div. 1 and 2, most scholarships are split among two or more swimmers (I don't know how NAIA schools do this but it likely similar). Only the very, very elite get a solo scholarship. Depending on how one interprets the word "Christian," I would say that there are no "Christian" D1 schools offering men's swimming scholarships. Those who include Catholic institutions in this category would disagree. In D2, there are maybe 4-6. In NAIA, perhaps 8-10.
You may want to consider D3 schools for swimming. If you check out the times, you will see that D3 times are mostly faster than D2 times. My son swam D3 (at Grove City College, a great "Christian" school) and had a wonderful experience (but no athletic scholarship).
If you sent me in a personal message your son's times, I might be able to give you more specific information.
Here's a quote from an athletic scholarship research service: "There are 142 division 1 and 50 division 2 colleges that offer swimming scholarships to Men. There are 185 division 1 and 64 division 2 colleges that offer scholarships to women. That’s a total of 1,810.8 swimming and diving scholarships for men in the NCAA alone. For women the total number in the NCAA is 3,108.4."