Several caveats seem to be in order.
First, both tax credits and vouchers contribute to the furthering of the myth of governmental responsibility for the education of our children. Each implies some form of ultimate governmental authorization or approval, if only in the fact that parents who appeal to either of these vehicles are seeking some kind of advantage or opportunity that they can only gain from state or federal authorities. This is to continue on the manifestly disastrous tack that allows government to be the final arbiter in matters of educational policy-making. Similarly, both tuition tax credits and vouchers run the risk of creating dependencies that Christian parents and Christian schools may not be able to survive without, should they ever be withdrawn. For schools that become dependent upon vouchers as a source of financial undergirding, there could develop a similar tendency to follow the trends of the competition, rather than to strive for Christian excellence regardless of what our secular counterparts might be trying or doing.